使用C#+FFmpeg+DirectX+dxva2硬體解碼播放h264流
阿新 • • 發佈：2019-11-23
本文門檻較高，因此行文看起來會亂一些，如果你看到某處能會心一笑請馬上聯絡我開始擺龍門陣
如果你跟隨這篇文章實現了播放器，那你會得到一個高效率，低cpu佔用（單路720p視訊解碼播放佔用1%左右cpu），且程式碼和引用精簡（無其他託管和非託管的dll依賴，更無需安裝任何外掛，你的程式完全綠色執行）；並且如果硬解不可用，切換到軟體是自動過程
首先需要準備好visual studio/msys2/ffmpeg原始碼/dx9sdk。因為我們要自己編譯ffmpeg，並且是改動程式碼後編譯，ffmpeg我們編譯時會裁剪。
- ffmpeg原始碼大家使用4.2.1，和我保持同步，這樣比較好對應，下載地址為ffmpeg-4.2.1.tar.gz
- msys2安裝好後不需要裝mingw和其他東西，只需要安裝make（見下方圖片；我們編譯工具鏈會用msvc而非mingw-gcc）
- visual studio版本按道理是不需要新版本的，應該是2008-2019都可以（不過還是得看看ffmpeg程式碼裡是否用了c99 c11等低版本不支援的東西），vs需要安裝c++和c#的模組（見下方圖片；應該也不需要特意去開啟什麼功能）
- dx9的sdk理論上是不用安裝的（如果你是高手，可以用c#的ilgenerator直接寫calli；亦或者寫unsafe程式碼直接進行記憶體call，文章最後我會為大家揭祕如何用c#呼叫c++甚至com元件）。我用了directx的managecode，由官方為我們做了dx的呼叫（見下方圖片）
第二步是修改ffmpeg原始碼並編譯，我們要修改的原始碼只有一個檔案的十餘行，而且是增量修改。
修改的檔案位於libavutil/hwcontext_dxva2.c檔案，我先將修改部分貼出來然後再給大家解釋
hwcontext_dxva2.c修改部分
static int dxva2_device_create9_extend(AVHWDeviceContext ctx, UINT adapter, HWND hWnd)
{
DXVA2DevicePriv priv = ctx->user_opaque;
D3DPRESENT_PARAMETERS d3dpp = {0};
D3DDISPLAYMODE d3ddm;
HRESULT hr;
pDirect3DCreate9 createD3D = (pDirect3DCreate9 )dlsym(priv->d3dlib, "Direct3DCreate9");
if (!createD3D) {
av_log(ctx, AV_LOG_ERROR, "Failed to locate Direct3DCreate9\n");
return AVERROR_UNKNOWN;
}
priv->d3d9 = createD3D(D3D_SDK_VERSION);
if (!priv->d3d9) {
av_log(ctx, AV_LOG_ERROR, "Failed to create IDirect3D object\n");
return AVERROR_UNKNOWN;
}
IDirect3D9_GetAdapterDisplayMode(priv->d3d9, adapter, &d3ddm);
d3dpp.BackBufferFormat = d3ddm.Format;
d3dpp.Windowed = TRUE; // 是否視窗顯示
d3dpp.hDeviceWindow = hWnd; // 顯示視窗控制代碼
d3dpp.SwapEffect = D3DSWAPEFFECT_DISCARD; // 交換鏈設定，後臺緩衝使用後直接丟棄
d3dpp.Flags = D3DPRESENTFLAG_VIDEO; // 附加特性，顯示視訊
DWORD behaviorFlags = D3DCREATE_MULTITHREADED | D3DCREATE_FPU_PRESERVE;
D3DDEVTYPE devType = D3DDEVTYPE_HAL;
D3DCAPS9 caps;
if (IDirect3D9_GetDeviceCaps(priv->d3d9, D3DADAPTER_DEFAULT, devType, &caps) >= 0)
{
if (caps.DevCaps & D3DDEVCAPS_HWTRANSFORMANDLIGHT)
{
behaviorFlags |= D3DCREATE_HARDWARE_VERTEXPROCESSING;
}
else
{
behaviorFlags |= D3DCREATE_SOFTWARE_VERTEXPROCESSING;
}
}
if(!hWnd)
hWnd = GetDesktopWindow();
hr = IDirect3D9_CreateDevice(priv->d3d9, adapter, D3DDEVTYPE_HAL, hWnd,
behaviorFlags,
&d3dpp, &priv->d3d9device);
if (FAILED(hr)) {
av_log(ctx, AV_LOG_ERROR, "Failed to create Direct3D device\n");
return AVERROR_UNKNOWN;
}
return 0;}
static int dxva2_device_create(AVHWDeviceContext ctx, const char device,
AVDictionary opts, int flags)
{
AVDXVA2DeviceContext hwctx = ctx->hwctx;
DXVA2DevicePriv priv;
pCreateDeviceManager9 createDeviceManager = NULL;
unsigned resetToken = 0;
UINT adapter = D3DADAPTER_DEFAULT;
HRESULT hr;
int err;
AVDictionaryEntry *t = NULL;
HWND hWnd = NULL;
if (device)
adapter = atoi(device);
priv = av_mallocz(sizeof(*priv));
if (!priv)
return AVERROR(ENOMEM);
ctx->user_opaque = priv;
ctx->free = dxva2_device_free;
priv->device_handle = INVALID_HANDLE_VALUE;
priv->d3dlib = dlopen("d3d9.dll", 0);
if (!priv->d3dlib) {
av_log(ctx, AV_LOG_ERROR, "Failed to load D3D9 library\n");
return AVERROR_UNKNOWN;
}
priv->dxva2lib = dlopen("dxva2.dll", 0);
if (!priv->dxva2lib) {
av_log(ctx, AV_LOG_ERROR, "Failed to load DXVA2 library\n");
return AVERROR_UNKNOWN;
}
createDeviceManager = (pCreateDeviceManager9 *)dlsym(priv->dxva2lib,
"DXVA2CreateDirect3DDeviceManager9");
if (!createDeviceManager) {
av_log(ctx, AV_LOG_ERROR, "Failed to locate DXVA2CreateDirect3DDeviceManager9\n");
return AVERROR_UNKNOWN;
}
t = av_dict_get(opts, "hWnd", NULL, 0);
if(t) {
hWnd = (HWND)atoi(t->value);
}
if(hWnd) {
if((err = dxva2_device_create9_extend(ctx, adapter, hWnd)) < 0)
return err;
} else {
if (dxva2_device_create9ex(ctx, adapter) < 0) {
// Retry with "classic" d3d9
err = dxva2_device_create9(ctx, adapter);
if (err < 0)
return err;
}
}
hr = createDeviceManager(&resetToken, &hwctx->devmgr);
if (FAILED(hr)) {
av_log(ctx, AV_LOG_ERROR, "Failed to create Direct3D device manager\n");
return AVERROR_UNKNOWN;
}
hr = IDirect3DDeviceManager9_ResetDevice(hwctx->devmgr, priv->d3d9device, resetToken);
if (FAILED(hr)) {
av_log(ctx, AV_LOG_ERROR, "Failed to bind Direct3D device to device manager\n");
return AVERROR_UNKNOWN;
}
hr = IDirect3DDeviceManager9_OpenDeviceHandle(hwctx->devmgr, &priv->device_handle);
if (FAILED(hr)) {
av_log(ctx, AV_LOG_ERROR, "Failed to open device handle\n");
return AVERROR_UNKNOWN;
}
return 0;}
程式碼中dxva2_device_create9_extend函式是我新加入的，並且在dxva2_device_create函式（這個函式是ffmpeg原始流程中的，我的改動不影響原本任何功能）中適時呼叫；簡單來說，原來的ffmpeg也能基於dxva2硬體解碼，但是它沒法將解碼得到的surface用於前臺播放，因為它建立device時並未指定視窗和其他相關引數，大家可以參考我程式碼實現，我將視窗控制代碼傳入後建立過程完全改變（其他人如果使用我們編譯的程式碼，他沒有傳入視窗控制代碼，就執行原來的建立，因此百分百相容）。
原始檔案(版本不一致，僅供參考)
（ps：在這裡我講一下網路上另外一種寫法（兩年前我也用的他們的，因為沒時間詳細看ffmpeg原始碼），他們是在外面建立的device和surface然後想辦法傳到ffmpeg內部進行替換，這樣做有好處，就是不用自己修改和編譯ffmpeg，壞處是得自己維護device和surface。至於二進位制相容方面考慮，兩種做法都不是太好）
程式碼修改完成後我們使用msys2編譯
- 首先是需要把編譯器設定為msvc，這個步驟通過使用vs的命令列工具即可，如下圖
- 然後是設定msys2繼承環境變數（這樣make時才能找到cl/link）
- 開啟msys，檢視變數是否正確
- 編譯ffmpeg
./configure --enable-shared --enable-small --disable-all --disable-autodetect --enable-avcodec --enable-decoder=h264 --enable-dxva2 --enable-hwaccel=h264_dxva2 --toolchain=msvc --prefix=host
make && make install
編譯完成後標頭檔案和dll在host資料夾內（編譯產出的dll也是clear的，不依賴msvc**.dll）
在C#中使用我們產出的方式需要使用p/invoke和unsafe程式碼。
我先貼出我針對ffmpeg寫的一個工具類，然後給大家稍微講解一下
FFHelper.cs
using System;
using System.Runtime.InteropServices;
namespace MultiPlayer
{
public enum AVCodecID
{
AV_CODEC_ID_NONE,
/* video codecs */
AV_CODEC_ID_MPEG1VIDEO,
AV_CODEC_ID_MPEG2VIDEO, ///< preferred ID for MPEG-1/2 video decoding
AV_CODEC_ID_H261,
AV_CODEC_ID_H263,
AV_CODEC_ID_RV10,
AV_CODEC_ID_RV20,
AV_CODEC_ID_MJPEG,
AV_CODEC_ID_MJPEGB,
AV_CODEC_ID_LJPEG,
AV_CODEC_ID_SP5X,
AV_CODEC_ID_JPEGLS,
AV_CODEC_ID_MPEG4,
AV_CODEC_ID_RAWVIDEO,
AV_CODEC_ID_MSMPEG4V1,
AV_CODEC_ID_MSMPEG4V2,
AV_CODEC_ID_MSMPEG4V3,
AV_CODEC_ID_WMV1,
AV_CODEC_ID_WMV2,
AV_CODEC_ID_H263P,
AV_CODEC_ID_H263I,
AV_CODEC_ID_FLV1,
AV_CODEC_ID_SVQ1,
AV_CODEC_ID_SVQ3,
AV_CODEC_ID_DVVIDEO,
AV_CODEC_ID_HUFFYUV,
AV_CODEC_ID_CYUV,
AV_CODEC_ID_H264,
AV_CODEC_ID_INDEO3,
AV_CODEC_ID_VP3,
AV_CODEC_ID_THEORA,
AV_CODEC_ID_ASV1,
AV_CODEC_ID_ASV2,
AV_CODEC_ID_FFV1,
AV_CODEC_ID_4XM,
AV_CODEC_ID_VCR1,
AV_CODEC_ID_CLJR,
AV_CODEC_ID_MDEC,
AV_CODEC_ID_ROQ,
AV_CODEC_ID_INTERPLAY_VIDEO,
AV_CODEC_ID_XAN_WC3,
AV_CODEC_ID_XAN_WC4,
AV_CODEC_ID_RPZA,
AV_CODEC_ID_CINEPAK,
AV_CODEC_ID_WS_VQA,
AV_CODEC_ID_MSRLE,
AV_CODEC_ID_MSVIDEO1,
AV_CODEC_ID_IDCIN,
AV_CODEC_ID_8BPS,
AV_CODEC_ID_SMC,
AV_CODEC_ID_FLIC,
AV_CODEC_ID_TRUEMOTION1,
AV_CODEC_ID_VMDVIDEO,
AV_CODEC_ID_MSZH,
AV_CODEC_ID_ZLIB,
AV_CODEC_ID_QTRLE,
AV_CODEC_ID_TSCC,
AV_CODEC_ID_ULTI,
AV_CODEC_ID_QDRAW,
AV_CODEC_ID_VIXL,
AV_CODEC_ID_QPEG,
AV_CODEC_ID_PNG,
AV_CODEC_ID_PPM,
AV_CODEC_ID_PBM,
AV_CODEC_ID_PGM,
AV_CODEC_ID_PGMYUV,
AV_CODEC_ID_PAM,
AV_CODEC_ID_FFVHUFF,
AV_CODEC_ID_RV30,
AV_CODEC_ID_RV40,
AV_CODEC_ID_VC1,
AV_CODEC_ID_WMV3,
AV_CODEC_ID_LOCO,
AV_CODEC_ID_WNV1,
AV_CODEC_ID_AASC,
AV_CODEC_ID_INDEO2,
AV_CODEC_ID_FRAPS,
AV_CODEC_ID_TRUEMOTION2,
AV_CODEC_ID_BMP,
AV_CODEC_ID_CSCD,
AV_CODEC_ID_MMVIDEO,
AV_CODEC_ID_ZMBV,
AV_CODEC_ID_AVS,
AV_CODEC_ID_SMACKVIDEO,
AV_CODEC_ID_NUV,
AV_CODEC_ID_KMVC,
AV_CODEC_ID_FLASHSV,
AV_CODEC_ID_CAVS,
AV_CODEC_ID_JPEG2000,
AV_CODEC_ID_VMNC,
AV_CODEC_ID_VP5,
AV_CODEC_ID_VP6,
AV_CODEC_ID_VP6F,
AV_CODEC_ID_TARGA,
AV_CODEC_ID_DSICINVIDEO,
AV_CODEC_ID_TIERTEXSEQVIDEO,
AV_CODEC_ID_TIFF,
AV_CODEC_ID_GIF,
AV_CODEC_ID_DXA,
AV_CODEC_ID_DNXHD,
AV_CODEC_ID_THP,
AV_CODEC_ID_SGI,
AV_CODEC_ID_C93,
AV_CODEC_ID_BETHSOFTVID,
AV_CODEC_ID_PTX,
AV_CODEC_ID_TXD,
AV_CODEC_ID_VP6A,
AV_CODEC_ID_AMV,
AV_CODEC_ID_VB,
AV_CODEC_ID_PCX,
AV_CODEC_ID_SUNRAST,
AV_CODEC_ID_INDEO4,
AV_CODEC_ID_INDEO5,
AV_CODEC_ID_MIMIC,
AV_CODEC_ID_RL2,
AV_CODEC_ID_ESCAPE124,
AV_CODEC_ID_DIRAC,
AV_CODEC_ID_BFI,
AV_CODEC_ID_CMV,
AV_CODEC_ID_MOTIONPIXELS,
AV_CODEC_ID_TGV,
AV_CODEC_ID_TGQ,
AV_CODEC_ID_TQI,
AV_CODEC_ID_AURA,
AV_CODEC_ID_AURA2,
AV_CODEC_ID_V210X,
AV_CODEC_ID_TMV,
AV_CODEC_ID_V210,
AV_CODEC_ID_DPX,
AV_CODEC_ID_MAD,
AV_CODEC_ID_FRWU,
AV_CODEC_ID_FLASHSV2,
AV_CODEC_ID_CDGRAPHICS,
AV_CODEC_ID_R210,
AV_CODEC_ID_ANM,
AV_CODEC_ID_BINKVIDEO,
AV_CODEC_ID_IFF_ILBM,
//#define AV_CODEC_ID_IFF_BYTERUN1 AV_CODEC_ID_IFF_ILBM
AV_CODEC_ID_KGV1,
AV_CODEC_ID_YOP,
AV_CODEC_ID_VP8,
AV_CODEC_ID_PICTOR,
AV_CODEC_ID_ANSI,
AV_CODEC_ID_A64_MULTI,
AV_CODEC_ID_A64_MULTI5,
AV_CODEC_ID_R10K,
AV_CODEC_ID_MXPEG,
AV_CODEC_ID_LAGARITH,
AV_CODEC_ID_PRORES,
AV_CODEC_ID_JV,
AV_CODEC_ID_DFA,
AV_CODEC_ID_WMV3IMAGE,
AV_CODEC_ID_VC1IMAGE,
AV_CODEC_ID_UTVIDEO,
AV_CODEC_ID_BMV_VIDEO,
AV_CODEC_ID_VBLE,
AV_CODEC_ID_DXTORY,
AV_CODEC_ID_V410,
AV_CODEC_ID_XWD,
AV_CODEC_ID_CDXL,
AV_CODEC_ID_XBM,
AV_CODEC_ID_ZEROCODEC,
AV_CODEC_ID_MSS1,
AV_CODEC_ID_MSA1,
AV_CODEC_ID_TSCC2,
AV_CODEC_ID_MTS2,
AV_CODEC_ID_CLLC,
AV_CODEC_ID_MSS2,
AV_CODEC_ID_VP9,
AV_CODEC_ID_AIC,
AV_CODEC_ID_ESCAPE130,
AV_CODEC_ID_G2M,
AV_CODEC_ID_WEBP,
AV_CODEC_ID_HNM4_VIDEO,
AV_CODEC_ID_HEVC,
//#define AV_CODEC_ID_H265 AV_CODEC_ID_HEVC
AV_CODEC_ID_FIC,
AV_CODEC_ID_ALIAS_PIX,
AV_CODEC_ID_BRENDER_PIX,
AV_CODEC_ID_PAF_VIDEO,
AV_CODEC_ID_EXR,
AV_CODEC_ID_VP7,
AV_CODEC_ID_SANM,
AV_CODEC_ID_SGIRLE,
AV_CODEC_ID_MVC1,
AV_CODEC_ID_MVC2,
AV_CODEC_ID_HQX,
AV_CODEC_ID_TDSC,
AV_CODEC_ID_HQ_HQA,
AV_CODEC_ID_HAP,
AV_CODEC_ID_DDS,
AV_CODEC_ID_DXV,
AV_CODEC_ID_SCREENPRESSO,
AV_CODEC_ID_RSCC,
AV_CODEC_ID_AVS2,
AV_CODEC_ID_Y41P = 0x8000,
AV_CODEC_ID_AVRP,
AV_CODEC_ID_012V,
AV_CODEC_ID_AVUI,
AV_CODEC_ID_AYUV,
AV_CODEC_ID_TARGA_Y216,
AV_CODEC_ID_V308,
AV_CODEC_ID_V408,
AV_CODEC_ID_YUV4,
AV_CODEC_ID_AVRN,
AV_CODEC_ID_CPIA,
AV_CODEC_ID_XFACE,
AV_CODEC_ID_SNOW,
AV_CODEC_ID_SMVJPEG,
AV_CODEC_ID_APNG,
AV_CODEC_ID_DAALA,
AV_CODEC_ID_CFHD,
AV_CODEC_ID_TRUEMOTION2RT,
AV_CODEC_ID_M101,
AV_CODEC_ID_MAGICYUV,
AV_CODEC_ID_SHEERVIDEO,
AV_CODEC_ID_YLC,
AV_CODEC_ID_PSD,
AV_CODEC_ID_PIXLET,
AV_CODEC_ID_SPEEDHQ,
AV_CODEC_ID_FMVC,
AV_CODEC_ID_SCPR,
AV_CODEC_ID_CLEARVIDEO,
AV_CODEC_ID_XPM,
AV_CODEC_ID_AV1,
AV_CODEC_ID_BITPACKED,
AV_CODEC_ID_MSCC,
AV_CODEC_ID_SRGC,
AV_CODEC_ID_SVG,
AV_CODEC_ID_GDV,
AV_CODEC_ID_FITS,
AV_CODEC_ID_IMM4,
AV_CODEC_ID_PROSUMER,
AV_CODEC_ID_MWSC,
AV_CODEC_ID_WCMV,
AV_CODEC_ID_RASC,
AV_CODEC_ID_HYMT,
AV_CODEC_ID_ARBC,
AV_CODEC_ID_AGM,
AV_CODEC_ID_LSCR,
AV_CODEC_ID_VP4,
/* various PCM "codecs" */
AV_CODEC_ID_FIRST_AUDIO = 0x10000, ///< A dummy id pointing at the start of audio codecs
AV_CODEC_ID_PCM_S16LE = 0x10000,
AV_CODEC_ID_PCM_S16BE,
AV_CODEC_ID_PCM_U16LE,
AV_CODEC_ID_PCM_U16BE,
AV_CODEC_ID_PCM_S8,
AV_CODEC_ID_PCM_U8,
AV_CODEC_ID_PCM_MULAW,
AV_CODEC_ID_PCM_ALAW,
AV_CODEC_ID_PCM_S32LE,
AV_CODEC_ID_PCM_S32BE,
AV_CODEC_ID_PCM_U32LE,
AV_CODEC_ID_PCM_U32BE,
AV_CODEC_ID_PCM_S24LE,
AV_CODEC_ID_PCM_S24BE,
AV_CODEC_ID_PCM_U24LE,
AV_CODEC_ID_PCM_U24BE,
AV_CODEC_ID_PCM_S24DAUD,
AV_CODEC_ID_PCM_ZORK,
AV_CODEC_ID_PCM_S16LE_PLANAR,
AV_CODEC_ID_PCM_DVD,
AV_CODEC_ID_PCM_F32BE,
AV_CODEC_ID_PCM_F32LE,
AV_CODEC_ID_PCM_F64BE,
AV_CODEC_ID_PCM_F64LE,
AV_CODEC_ID_PCM_BLURAY,
AV_CODEC_ID_PCM_LXF,
AV_CODEC_ID_S302M,
AV_CODEC_ID_PCM_S8_PLANAR,
AV_CODEC_ID_PCM_S24LE_PLANAR,
AV_CODEC_ID_PCM_S32LE_PLANAR,
AV_CODEC_ID_PCM_S16BE_PLANAR,
AV_CODEC_ID_PCM_S64LE = 0x10800,
AV_CODEC_ID_PCM_S64BE,
AV_CODEC_ID_PCM_F16LE,
AV_CODEC_ID_PCM_F24LE,
AV_CODEC_ID_PCM_VIDC,
/* various ADPCM codecs */
AV_CODEC_ID_ADPCM_IMA_QT = 0x11000,
AV_CODEC_ID_ADPCM_IMA_WAV,
AV_CODEC_ID_ADPCM_IMA_DK3,
AV_CODEC_ID_ADPCM_IMA_DK4,
AV_CODEC_ID_ADPCM_IMA_WS,
AV_CODEC_ID_ADPCM_IMA_SMJPEG,
AV_CODEC_ID_ADPCM_MS,
AV_CODEC_ID_ADPCM_4XM,
AV_CODEC_ID_ADPCM_XA,
AV_CODEC_ID_ADPCM_ADX,
AV_CODEC_ID_ADPCM_EA,
AV_CODEC_ID_ADPCM_G726,
AV_CODEC_ID_ADPCM_CT,
AV_CODEC_ID_ADPCM_SWF,
AV_CODEC_ID_ADPCM_YAMAHA,
AV_CODEC_ID_ADPCM_SBPRO_4,
AV_CODEC_ID_ADPCM_SBPRO_3,
AV_CODEC_ID_ADPCM_SBPRO_2,
AV_CODEC_ID_ADPCM_THP,
AV_CODEC_ID_ADPCM_IMA_AMV,
AV_CODEC_ID_ADPCM_EA_R1,
AV_CODEC_ID_ADPCM_EA_R3,
AV_CODEC_ID_ADPCM_EA_R2,
AV_CODEC_ID_ADPCM_IMA_EA_SEAD,
AV_CODEC_ID_ADPCM_IMA_EA_EACS,
AV_CODEC_ID_ADPCM_EA_XAS,
AV_CODEC_ID_ADPCM_EA_MAXIS_XA,
AV_CODEC_ID_ADPCM_IMA_ISS,
AV_CODEC_ID_ADPCM_G722,
AV_CODEC_ID_ADPCM_IMA_APC,
AV_CODEC_ID_ADPCM_VIMA,
AV_CODEC_ID_ADPCM_AFC = 0x11800,
AV_CODEC_ID_ADPCM_IMA_OKI,
AV_CODEC_ID_ADPCM_DTK,
AV_CODEC_ID_ADPCM_IMA_RAD,
AV_CODEC_ID_ADPCM_G726LE,
AV_CODEC_ID_ADPCM_THP_LE,
AV_CODEC_ID_ADPCM_PSX,
AV_CODEC_ID_ADPCM_AICA,
AV_CODEC_ID_ADPCM_IMA_DAT4,
AV_CODEC_ID_ADPCM_MTAF,
AV_CODEC_ID_ADPCM_AGM,
/* AMR */
AV_CODEC_ID_AMR_NB = 0x12000,
AV_CODEC_ID_AMR_WB,
/* RealAudio codecs*/
AV_CODEC_ID_RA_144 = 0x13000,
AV_CODEC_ID_RA_288,
/* various DPCM codecs */
AV_CODEC_ID_ROQ_DPCM = 0x14000,
AV_CODEC_ID_INTERPLAY_DPCM,
AV_CODEC_ID_XAN_DPCM,
AV_CODEC_ID_SOL_DPCM,
AV_CODEC_ID_SDX2_DPCM = 0x14800,
AV_CODEC_ID_GREMLIN_DPCM,
/* audio codecs */
AV_CODEC_ID_MP2 = 0x15000,
AV_CODEC_ID_MP3, ///< preferred ID for decoding MPEG audio layer 1, 2 or 3
AV_CODEC_ID_AAC,
AV_CODEC_ID_AC3,
AV_CODEC_ID_DTS,
AV_CODEC_ID_VORBIS,
AV_CODEC_ID_DVAUDIO,
AV_CODEC_ID_WMAV1,
AV_CODEC_ID_WMAV2,
AV_CODEC_ID_MACE3,
AV_CODEC_ID_MACE6,
AV_CODEC_ID_VMDAUDIO,
AV_CODEC_ID_FLAC,
AV_CODEC_ID_MP3ADU,
AV_CODEC_ID_MP3ON4,
AV_CODEC_ID_SHORTEN,
AV_CODEC_ID_ALAC,
AV_CODEC_ID_WESTWOOD_SND1,
AV_CODEC_ID_GSM, ///< as in Berlin toast format
AV_CODEC_ID_QDM2,
AV_CODEC_ID_COOK,
AV_CODEC_ID_TRUESPEECH,
AV_CODEC_ID_TTA,
AV_CODEC_ID_SMACKAUDIO,
AV_CODEC_ID_QCELP,
AV_CODEC_ID_WAVPACK,
AV_CODEC_ID_DSICINAUDIO,
AV_CODEC_ID_IMC,
AV_CODEC_ID_MUSEPACK7,
AV_CODEC_ID_MLP,
AV_CODEC_ID_GSM_MS, /* as found in WAV */
AV_CODEC_ID_ATRAC3,
AV_CODEC_ID_APE,
AV_CODEC_ID_NELLYMOSER,
AV_CODEC_ID_MUSEPACK8,
AV_CODEC_ID_SPEEX,
AV_CODEC_ID_WMAVOICE,
AV_CODEC_ID_WMAPRO,
AV_CODEC_ID_WMALOSSLESS,
AV_CODEC_ID_ATRAC3P,
AV_CODEC_ID_EAC3,
AV_CODEC_ID_SIPR,
AV_CODEC_ID_MP1,
AV_CODEC_ID_TWINVQ,
AV_CODEC_ID_TRUEHD,
AV_CODEC_ID_MP4ALS,
AV_CODEC_ID_ATRAC1,
AV_CODEC_ID_BINKAUDIO_RDFT,
AV_CODEC_ID_BINKAUDIO_DCT,
AV_CODEC_ID_AAC_LATM,
AV_CODEC_ID_QDMC,
AV_CODEC_ID_CELT,
AV_CODEC_ID_G723_1,
AV_CODEC_ID_G729,
AV_CODEC_ID_8SVX_EXP,
AV_CODEC_ID_8SVX_FIB,
AV_CODEC_ID_BMV_AUDIO,
AV_CODEC_ID_RALF,
AV_CODEC_ID_IAC,
AV_CODEC_ID_ILBC,
AV_CODEC_ID_OPUS,
AV_CODEC_ID_COMFORT_NOISE,
AV_CODEC_ID_TAK,
AV_CODEC_ID_METASOUND,
AV_CODEC_ID_PAF_AUDIO,
AV_CODEC_ID_ON2AVC,
AV_CODEC_ID_DSS_SP,
AV_CODEC_ID_CODEC2,
AV_CODEC_ID_FFWAVESYNTH = 0x15800,
AV_CODEC_ID_SONIC,
AV_CODEC_ID_SONIC_LS,
AV_CODEC_ID_EVRC,
AV_CODEC_ID_SMV,
AV_CODEC_ID_DSD_LSBF,
AV_CODEC_ID_DSD_MSBF,
AV_CODEC_ID_DSD_LSBF_PLANAR,
AV_CODEC_ID_DSD_MSBF_PLANAR,
AV_CODEC_ID_4GV,
AV_CODEC_ID_INTERPLAY_ACM,
AV_CODEC_ID_XMA1,
AV_CODEC_ID_XMA2,
AV_CODEC_ID_DST,
AV_CODEC_ID_ATRAC3AL,
AV_CODEC_ID_ATRAC3PAL,
AV_CODEC_ID_DOLBY_E,
AV_CODEC_ID_APTX,
AV_CODEC_ID_APTX_HD,
AV_CODEC_ID_SBC,
AV_CODEC_ID_ATRAC9,
AV_CODEC_ID_HCOM,
/* subtitle codecs */
AV_CODEC_ID_FIRST_SUBTITLE = 0x17000, ///< A dummy ID pointing at the start of subtitle codecs.
AV_CODEC_ID_DVD_SUBTITLE = 0x17000,
AV_CODEC_ID_DVB_SUBTITLE,
AV_CODEC_ID_TEXT, ///< raw UTF-8 text
AV_CODEC_ID_XSUB,
AV_CODEC_ID_SSA,
AV_CODEC_ID_MOV_TEXT,
AV_CODEC_ID_HDMV_PGS_SUBTITLE,
AV_CODEC_ID_DVB_TELETEXT,
AV_CODEC_ID_SRT,
AV_CODEC_ID_MICRODVD = 0x17800,
AV_CODEC_ID_EIA_608,
AV_CODEC_ID_JACOSUB,
AV_CODEC_ID_SAMI,
AV_CODEC_ID_REALTEXT,
AV_CODEC_ID_STL,
AV_CODEC_ID_SUBVIEWER1,
AV_CODEC_ID_SUBVIEWER,
AV_CODEC_ID_SUBRIP,
AV_CODEC_ID_WEBVTT,
AV_CODEC_ID_MPL2,
AV_CODEC_ID_VPLAYER,
AV_CODEC_ID_PJS,
AV_CODEC_ID_ASS,
AV_CODEC_ID_HDMV_TEXT_SUBTITLE,
AV_CODEC_ID_TTML,
AV_CODEC_ID_ARIB_CAPTION,
/* other specific kind of codecs (generally used for attachments) */
AV_CODEC_ID_FIRST_UNKNOWN = 0x18000, ///< A dummy ID pointing at the start of various fake codecs.
AV_CODEC_ID_TTF = 0x18000,
AV_CODEC_ID_SCTE_35, ///< Contain timestamp estimated through PCR of program stream.
AV_CODEC_ID_BINTEXT = 0x18800,
AV_CODEC_ID_XBIN,
AV_CODEC_ID_IDF,
AV_CODEC_ID_OTF,
AV_CODEC_ID_SMPTE_KLV,
AV_CODEC_ID_DVD_NAV,
AV_CODEC_ID_TIMED_ID3,
AV_CODEC_ID_BIN_DATA,
AV_CODEC_ID_PROBE = 0x19000, ///< codec_id is not known (like AV_CODEC_ID_NONE) but lavf should attempt to identify it
AV_CODEC_ID_MPEG2TS = 0x20000, /**< _FAKE_ codec to indicate a raw MPEG-2 TS
* stream (only used by libavformat) */
AV_CODEC_ID_MPEG4SYSTEMS = 0x20001, /**< _FAKE_ codec to indicate a MPEG-4 Systems
* stream (only used by libavformat) */
AV_CODEC_ID_FFMETADATA = 0x21000, ///< Dummy codec for streams containing only metadata information.
AV_CODEC_ID_WRAPPED_AVFRAME = 0x21001, ///< Passthrough codec, AVFrames wrapped in AVPacket
}
public enum AVHWDeviceType
{
AV_HWDEVICE_TYPE_NONE,
AV_HWDEVICE_TYPE_VDPAU,
AV_HWDEVICE_TYPE_CUDA,
AV_HWDEVICE_TYPE_VAAPI,
AV_HWDEVICE_TYPE_DXVA2,
AV_HWDEVICE_TYPE_QSV,
AV_HWDEVICE_TYPE_VIDEOTOOLBOX,
AV_HWDEVICE_TYPE_D3D11VA,
AV_HWDEVICE_TYPE_DRM,
AV_HWDEVICE_TYPE_OPENCL,
AV_HWDEVICE_TYPE_MEDIACODEC,
}
public enum AVPixelFormat
{
AV_PIX_FMT_NONE = -1,
AV_PIX_FMT_YUV420P, ///< planar YUV 4:2:0, 12bpp, (1 Cr & Cb sample per 2x2 Y samples)
AV_PIX_FMT_YUYV422, ///< packed YUV 4:2:2, 16bpp, Y0 Cb Y1 Cr
AV_PIX_FMT_RGB24, ///< packed RGB 8:8:8, 24bpp, RGBRGB...
AV_PIX_FMT_BGR24, ///< packed RGB 8:8:8, 24bpp, BGRBGR...
AV_PIX_FMT_YUV422P, ///< planar YUV 4:2:2, 16bpp, (1 Cr & Cb sample per 2x1 Y samples)
AV_PIX_FMT_YUV444P, ///< planar YUV 4:4:4, 24bpp, (1 Cr & Cb sample per 1x1 Y samples)
AV_PIX_FMT_YUV410P, ///< planar YUV 4:1:0, 9bpp, (1 Cr & Cb sample per 4x4 Y samples)
AV_PIX_FMT_YUV411P, ///< planar YUV 4:1:1, 12bpp, (1 Cr & Cb sample per 4x1 Y samples)
AV_PIX_FMT_GRAY8, ///< Y , 8bpp
AV_PIX_FMT_MONOWHITE, ///< Y , 1bpp, 0 is white, 1 is black, in each byte pixels are ordered from the msb to the lsb
AV_PIX_FMT_MONOBLACK, ///< Y , 1bpp, 0 is black, 1 is white, in each byte pixels are ordered from the msb to the lsb
AV_PIX_FMT_PAL8, ///< 8 bits with AV_PIX_FMT_RGB32 palette
AV_PIX_FMT_YUVJ420P, ///< planar YUV 4:2:0, 12bpp, full scale (JPEG), deprecated in favor of AV_PIX_FMT_YUV420P and setting color_range
AV_PIX_FMT_YUVJ422P, ///< planar YUV 4:2:2, 16bpp, full scale (JPEG), deprecated in favor of AV_PIX_FMT_YUV422P and setting color_range
AV_PIX_FMT_YUVJ444P, ///< planar YUV 4:4:4, 24bpp, full scale (JPEG), deprecated in favor of AV_PIX_FMT_YUV444P and setting color_range
AV_PIX_FMT_UYVY422, ///< packed YUV 4:2:2, 16bpp, Cb Y0 Cr Y1
AV_PIX_FMT_UYYVYY411, ///< packed YUV 4:1:1, 12bpp, Cb Y0 Y1 Cr Y2 Y3
AV_PIX_FMT_BGR8, ///< packed RGB 3:3:2, 8bpp, (msb)2B 3G 3R(lsb)
AV_PIX_FMT_BGR4, ///< packed RGB 1:2:1 bitstream, 4bpp, (msb)1B 2G 1R(lsb), a byte contains two pixels, the first pixel in the byte is the one composed by the 4 msb bits
AV_PIX_FMT_BGR4_BYTE, ///< packed RGB 1:2:1, 8bpp, (msb)1B 2G 1R(lsb)
AV_PIX_FMT_RGB8, ///< packed RGB 3:3:2, 8bpp, (msb)2R 3G 3B(lsb)
AV_PIX_FMT_RGB4, ///< packed RGB 1:2:1 bitstream, 4bpp, (msb)1R 2G 1B(lsb), a byte contains two pixels, the first pixel in the byte is the one composed by the 4 msb bits
AV_PIX_FMT_RGB4_BYTE, ///< packed RGB 1:2:1, 8bpp, (msb)1R 2G 1B(lsb)
AV_PIX_FMT_NV12, ///< planar YUV 4:2:0, 12bpp, 1 plane for Y and 1 plane for the UV components, which are interleaved (first byte U and the following byte V)
AV_PIX_FMT_NV21, ///< as above, but U and V bytes are swapped
AV_PIX_FMT_ARGB, ///< packed ARGB 8:8:8:8, 32bpp, ARGBARGB...
AV_PIX_FMT_RGBA, ///< packed RGBA 8:8:8:8, 32bpp, RGBARGBA...
AV_PIX_FMT_ABGR, ///< packed ABGR 8:8:8:8, 32bpp, ABGRABGR...
AV_PIX_FMT_BGRA, ///< packed BGRA 8:8:8:8, 32bpp, BGRABGRA...
AV_PIX_FMT_GRAY16BE, ///< Y , 16bpp, big-endian
AV_PIX_FMT_GRAY16LE, ///< Y , 16bpp, little-endian
AV_PIX_FMT_YUV440P, ///< planar YUV 4:4:0 (1 Cr & Cb sample per 1x2 Y samples)
AV_PIX_FMT_YUVJ440P, ///< planar YUV 4:4:0 full scale (JPEG), deprecated in favor of AV_PIX_FMT_YUV440P and setting color_range
AV_PIX_FMT_YUVA420P, ///< planar YUV 4:2:0, 20bpp, (1 Cr & Cb sample per 2x2 Y & A samples)
AV_PIX_FMT_RGB48BE, ///< packed RGB 16:16:16, 48bpp, 16R, 16G, 16B, the 2-byte value for each R/G/B component is stored as big-endian
AV_PIX_FMT_RGB48LE, ///< packed RGB 16:16:16, 48bpp, 16R, 16G, 16B, the 2-byte value for each R/G/B component is stored as little-endian
AV_PIX_FMT_RGB565BE, ///< packed RGB 5:6:5, 16bpp, (msb) 5R 6G 5B(lsb), big-endian
AV_PIX_FMT_RGB565LE, ///< packed RGB 5:6:5, 16bpp, (msb) 5R 6G 5B(lsb), little-endian
AV_PIX_FMT_RGB555BE, ///< packed RGB 5:5:5, 16bpp, (msb)1X 5R 5G 5B(lsb), big-endian , X=unused/undefined
AV_PIX_FMT_RGB555LE, ///< packed RGB 5:5:5, 16bpp, (msb)1X 5R 5G 5B(lsb), little-endian, X=unused/undefined
AV_PIX_FMT_BGR565BE, ///< packed BGR 5:6:5, 16bpp, (msb) 5B 6G 5R(lsb), big-endian
AV_PIX_FMT_BGR565LE, ///< packed BGR 5:6:5, 16bpp, (msb) 5B 6G 5R(lsb), little-endian
AV_PIX_FMT_BGR555BE, ///< packed BGR 5:5:5, 16bpp, (msb)1X 5B 5G 5R(lsb), big-endian , X=unused/undefined
AV_PIX_FMT_BGR555LE, ///< packed BGR 5:5:5, 16bpp, (msb)1X 5B 5G 5R(lsb), little-endian, X=unused/undefined
/** @name Deprecated pixel formats */
/**@{*/
AV_PIX_FMT_VAAPI_MOCO, ///< HW acceleration through VA API at motion compensation entry-point, Picture.data[3] contains a vaapi_render_state struct which contains macroblocks as well as various fields extracted from headers
AV_PIX_FMT_VAAPI_IDCT, ///< HW acceleration through VA API at IDCT entry-point, Picture.data[3] contains a vaapi_render_state struct which contains fields extracted from headers
AV_PIX_FMT_VAAPI_VLD, ///< HW decoding through VA API, Picture.data[3] contains a VASurfaceID
/**@}*/
AV_PIX_FMT_VAAPI = AV_PIX_FMT_VAAPI_VLD,
AV_PIX_FMT_YUV420P16LE, ///< planar YUV 4:2:0, 24bpp, (1 Cr & Cb sample per 2x2 Y samples), little-endian
AV_PIX_FMT_YUV420P16BE, ///< planar YUV 4:2:0, 24bpp, (1 Cr & Cb sample per 2x2 Y samples), big-endian
AV_PIX_FMT_YUV422P16LE, ///< planar YUV 4:2:2, 32bpp, (1 Cr & Cb sample per 2x1 Y samples), little-endian
AV_PIX_FMT_YUV422P16BE, ///< planar YUV 4:2:2, 32bpp, (1 Cr & Cb sample per 2x1 Y samples), big-endian
AV_PIX_FMT_YUV444P16LE, ///< planar YUV 4:4:4, 48bpp, (1 Cr & Cb sample per 1x1 Y samples), little-endian
AV_PIX_FMT_YUV444P16BE, ///< planar YUV 4:4:4, 48bpp, (1 Cr & Cb sample per 1x1 Y samples), big-endian
AV_PIX_FMT_DXVA2_VLD, ///< HW decoding through DXVA2, Picture.data[3] contains a LPDIRECT3DSURFACE9 pointer
AV_PIX_FMT_RGB444LE, ///< packed RGB 4:4:4, 16bpp, (msb)4X 4R 4G 4B(lsb), little-endian, X=unused/undefined
AV_PIX_FMT_RGB444BE, ///< packed RGB 4:4:4, 16bpp, (msb)4X 4R 4G 4B(lsb), big-endian, X=unused/undefined
AV_PIX_FMT_BGR444LE, ///< packed BGR 4:4:4, 16bpp, (msb)4X 4B 4G 4R(lsb), little-endian, X=unused/undefined
AV_PIX_FMT_BGR444BE, ///< packed BGR 4:4:4, 16bpp, (msb)4X 4B 4G 4R(lsb), big-endian, X=unused/undefined
AV_PIX_FMT_YA8, ///< 8 bits gray, 8 bits alpha
AV_PIX_FMT_Y400A = AV_PIX_FMT_YA8, ///< alias for AV_PIX_FMT_YA8
AV_PIX_FMT_GRAY8A = AV_PIX_FMT_YA8, ///< alias for AV_PIX_FMT_YA8
AV_PIX_FMT_BGR48BE, ///< packed RGB 16:16:16, 48bpp, 16B, 16G, 16R, the 2-byte value for each R/G/B component is stored as big-endian
AV_PIX_FMT_BGR48LE, ///< packed RGB 16:16:16, 48bpp, 16B, 16G, 16R, the 2-byte value for each R/G/B component is stored as little-endian
/**
* The following 12 formats have the disadvantage of needing 1 format for each bit depth.
* Notice that each 9/10 bits sample is stored in 16 bits with extra padding.
* If you want to support multiple bit depths, then using AV_PIX_FMT_YUV420P16* with the bpp stored separately is better.
*/
AV_PIX_FMT_YUV420P9BE, ///< planar YUV 4:2:0, 13.5bpp, (1 Cr & Cb sample per 2x2 Y samples), big-endian
AV_PIX_FMT_YUV420P9LE, ///< planar YUV 4:2:0, 13.5bpp, (1 Cr & Cb sample per 2x2 Y samples), little-endian
AV_PIX_FMT_YUV420P10BE,///< planar YUV 4:2:0, 15bpp, (1 Cr & Cb sample per 2x2 Y samples), big-endian
AV_PIX_FMT_YUV420P10LE,///< planar YUV 4:2:0, 15bpp, (1 Cr & Cb sample per 2x2 Y samples), little-endian
AV_PIX_FMT_YUV422P10BE,///< planar YUV 4:2:2, 20bpp, (1 Cr & Cb sample per 2x1 Y samples), big-endian
AV_PIX_FMT_YUV422P10LE,///< planar YUV 4:2:2, 20bpp, (1 Cr & Cb sample per 2x1 Y samples), little-endian
AV_PIX_FMT_YUV444P9BE, ///< planar YUV 4:4:4, 27bpp, (1 Cr & Cb sample per 1x1 Y samples), big-endian
AV_PIX_FMT_YUV444P9LE, ///< planar YUV 4:4:4, 27bpp, (1 Cr & Cb sample per 1x1 Y samples), little-endian
AV_PIX_FMT_YUV444P10BE,///< planar YUV 4:4:4, 30bpp, (1 Cr & Cb sample per 1x1 Y samples), big-endian
AV_PIX_FMT_YUV444P10LE,///< planar YUV 4:4:4, 30bpp, (1 Cr & Cb sample per 1x1 Y samples), little-endian
AV_PIX_FMT_YUV422P9BE, ///< planar YUV 4:2:2, 18bpp, (1 Cr & Cb sample per 2x1 Y samples), big-endian
AV_PIX_FMT_YUV422P9LE, ///< planar YUV 4:2:2, 18bpp, (1 Cr & Cb sample per 2x1 Y samples), little-endian
AV_PIX_FMT_GBRP, ///< planar GBR 4:4:4 24bpp
AV_PIX_FMT_GBR24P = AV_PIX_FMT_GBRP, // alias for #AV_PIX_FMT_GBRP
AV_PIX_FMT_GBRP9BE, ///< planar GBR 4:4:4 27bpp, big-endian
AV_PIX_FMT_GBRP9LE, ///< planar GBR 4:4:4 27bpp, little-endian
AV_PIX_FMT_GBRP10BE, ///< planar GBR 4:4:4 30bpp, big-endian
AV_PIX_FMT_GBRP10LE, ///< planar GBR 4:4:4 30bpp, little-endian
AV_PIX_FMT_GBRP16BE, ///< planar GBR 4:4:4 48bpp, big-endian
AV_PIX_FMT_GBRP16LE, ///< planar GBR 4:4:4 48bpp, little-endian
AV_PIX_FMT_YUVA422P, ///< planar YUV 4:2:2 24bpp, (1 Cr & Cb sample per 2x1 Y & A samples)
AV_PIX_FMT_YUVA444P, ///< planar YUV 4:4:4 32bpp, (1 Cr & Cb sample per 1x1 Y & A samples)
AV_PIX_FMT_YUVA420P9BE, ///< planar YUV 4:2:0 22.5bpp, (1 Cr & Cb sample per 2x2 Y & A samples), big-endian
AV_PIX_FMT_YUVA420P9LE, ///< planar YUV 4:2:0 22.5bpp, (1 Cr & Cb sample per 2x2 Y & A samples), little-endian
AV_PIX_FMT_YUVA422P9BE, ///< planar YUV 4:2:2 27bpp, (1 Cr & Cb sample per 2x1 Y & A samples), big-endian
AV_PIX_FMT_YUVA422P9LE, ///< planar YUV 4:2:2 27bpp, (1 Cr & Cb sample per 2x1 Y & A samples), little-endian
AV_PIX_FMT_YUVA444P9BE, ///< planar YUV 4:4:4 36bpp, (1 Cr & Cb sample per 1x1 Y & A samples), big-endian
AV_PIX_FMT_YUVA444P9LE, ///< planar YUV 4:4:4 36bpp, (1 Cr & Cb sample per 1x1 Y & A samples), little-endian
AV_PIX_FMT_YUVA420P10BE, ///< planar YUV 4:2:0 25bpp, (1 Cr & Cb sample per 2x2 Y & A samples, big-endian)
AV_PIX_FMT_YUVA420P10LE, ///< planar YUV 4:2:0 25bpp, (1 Cr & Cb sample per 2x2 Y & A samples, little-endian)
AV_PIX_FMT_YUVA422P10BE, ///< planar YUV 4:2:2 30bpp, (1 Cr & Cb sample per 2x1 Y & A samples, big-endian)
AV_PIX_FMT_YUVA422P10LE, ///< planar YUV 4:2:2 30bpp, (1 Cr & Cb sample per 2x1 Y & A samples, little-endian)
AV_PIX_FMT_YUVA444P10BE, ///< planar YUV 4:4:4 40bpp, (1 Cr & Cb sample per 1x1 Y & A samples, big-endian)
AV_PIX_FMT_YUVA444P10LE, ///< planar YUV 4:4:4 40bpp, (1 Cr & Cb sample per 1x1 Y & A samples, little-endian)
AV_PIX_FMT_YUVA420P16BE, ///< planar YUV 4:2:0 40bpp, (1 Cr & Cb sample per 2x2 Y & A samples, big-endian)
AV_PIX_FMT_YUVA420P16LE, ///< planar YUV 4:2:0 40bpp, (1 Cr & Cb sample per 2x2 Y & A samples, little-endian)
AV_PIX_FMT_YUVA422P16BE, ///< planar YUV 4:2:2 48bpp, (1 Cr & Cb sample per 2x1 Y & A samples, big-endian)
AV_PIX_FMT_YUVA422P16LE, ///< planar YUV 4:2:2 48bpp, (1 Cr & Cb sample per 2x1 Y & A samples, little-endian)
AV_PIX_FMT_YUVA444P16BE, ///< planar YUV 4:4:4 64bpp, (1 Cr & Cb sample per 1x1 Y & A samples, big-endian)
AV_PIX_FMT_YUVA444P16LE, ///< planar YUV 4:4:4 64bpp, (1 Cr & Cb sample per 1x1 Y & A samples, little-endian)
AV_PIX_FMT_VDPAU, ///< HW acceleration through VDPAU, Picture.data[3] contains a VdpVideoSurface
AV_PIX_FMT_XYZ12LE, ///< packed XYZ 4:4:4, 36 bpp, (msb) 12X, 12Y, 12Z (lsb), the 2-byte value for each X/Y/Z is stored as little-endian, the 4 lower bits are set to 0
AV_PIX_FMT_XYZ12BE, ///< packed XYZ 4:4:4, 36 bpp, (msb) 12X, 12Y, 12Z (lsb), the 2-byte value for each X/Y/Z is stored as big-endian, the 4 lower bits are set to 0
AV_PIX_FMT_NV16, ///< interleaved chroma YUV 4:2:2, 16bpp, (1 Cr & Cb sample per 2x1 Y samples)
AV_PIX_FMT_NV20LE, ///< interleaved chroma YUV 4:2:2, 20bpp, (1 Cr & Cb sample per 2x1 Y samples), little-endian
AV_PIX_FMT_NV20BE, ///< interleaved chroma YUV 4:2:2, 20bpp, (1 Cr & Cb sample per 2x1 Y samples), big-endian
AV_PIX_FMT_RGBA64BE, ///< packed RGBA 16:16:16:16, 64bpp, 16R, 16G, 16B, 16A, the 2-byte value for each R/G/B/A component is stored as big-endian
AV_PIX_FMT_RGBA64LE, ///< packed RGBA 16:16:16:16, 64bpp, 16R, 16G, 16B, 16A, the 2-byte value for each R/G/B/A component is stored as little-endian
AV_PIX_FMT_BGRA64BE, ///< packed RGBA 16:16:16:16, 64bpp, 16B, 16G, 16R, 16A, the 2-byte value for each R/G/B/A component is stored as big-endian
AV_PIX_FMT_BGRA64LE, ///< packed RGBA 16:16:16:16, 64bpp, 16B, 16G, 16R, 16A, the 2-byte value for each R/G/B/A component is stored as little-endian
AV_PIX_FMT_YVYU422, ///< packed YUV 4:2:2, 16bpp, Y0 Cr Y1 Cb
AV_PIX_FMT_YA16BE, ///< 16 bits gray, 16 bits alpha (big-endian)
AV_PIX_FMT_YA16LE, ///< 16 bits gray, 16 bits alpha (little-endian)
AV_PIX_FMT_GBRAP, ///< planar GBRA 4:4:4:4 32bpp
AV_PIX_FMT_GBRAP16BE, ///< planar GBRA 4:4:4:4 64bpp, big-endian
AV_PIX_FMT_GBRAP16LE, ///< planar GBRA 4:4:4:4 64bpp, little-endian
/**
* HW acceleration through QSV, data[3] contains a pointer to the
* mfxFrameSurface1 structure.
*/
AV_PIX_FMT_QSV,
/**
* HW acceleration though MMAL, data[3] contains a pointer to the
* MMAL_BUFFER_HEADER_T structure.
*/
AV_PIX_FMT_MMAL,
AV_PIX_FMT_D3D11VA_VLD, ///< HW decoding through Direct3D11 via old API, Picture.data[3] contains a ID3D11VideoDecoderOutputView pointer
/**
* HW acceleration through CUDA. data[i] contain CUdeviceptr pointers
* exactly as for system memory frames.
*/
AV_PIX_FMT_CUDA,
AV_PIX_FMT_0RGB, ///< packed RGB 8:8:8, 32bpp, XRGBXRGB... X=unused/undefined
AV_PIX_FMT_RGB0, ///< packed RGB 8:8:8, 32bpp, RGBXRGBX... X=unused/undefined
AV_PIX_FMT_0BGR, ///< packed BGR 8:8:8, 32bpp, XBGRXBGR... X=unused/undefined
AV_PIX_FMT_BGR0, ///< packed BGR 8:8:8, 32bpp, BGRXBGRX... X=unused/undefined
AV_PIX_FMT_YUV420P12BE, ///< planar YUV 4:2:0,18bpp, (1 Cr & Cb sample per 2x2 Y samples), big-endian
AV_PIX_FMT_YUV420P12LE, ///< planar YUV 4:2:0,18bpp, (1 Cr & Cb sample per 2x2 Y samples), little-endian
AV_PIX_FMT_YUV420P14BE, ///< planar YUV 4:2:0,21bpp, (1 Cr & Cb sample per 2x2 Y samples), big-endian
AV_PIX_FMT_YUV420P14LE, ///< planar YUV 4:2:0,21bpp, (1 Cr & Cb sample per 2x2 Y samples), little-endian
AV_PIX_FMT_YUV422P12BE, ///< planar YUV 4:2:2,24bpp, (1 Cr & Cb sample per 2x1 Y samples), big-endian
AV_PIX_FMT_YUV422P12LE, ///< planar YUV 4:2:2,24bpp, (1 Cr & Cb sample per 2x1 Y samples), little-endian
AV_PIX_FMT_YUV422P14BE, ///< planar YUV 4:2:2,28bpp, (1 Cr & Cb sample per 2x1 Y samples), big-endian
AV_PIX_FMT_YUV422P14LE, ///< planar YUV 4:2:2,28bpp, (1 Cr & Cb sample per 2x1 Y samples), little-endian
AV_PIX_FMT_YUV444P12BE, ///< planar YUV 4:4:4,36bpp, (1 Cr & Cb sample per 1x1 Y samples), big-endian
AV_PIX_FMT_YUV444P12LE, ///< planar YUV 4:4:4,36bpp, (1 Cr & Cb sample per 1x1 Y samples), little-endian
AV_PIX_FMT_YUV444P14BE, ///< planar YUV 4:4:4,42bpp, (1 Cr & Cb sample per 1x1 Y samples), big-endian
AV_PIX_FMT_YUV444P14LE, ///< planar YUV 4:4:4,42bpp, (1 Cr & Cb sample per 1x1 Y samples), little-endian
AV_PIX_FMT_GBRP12BE, ///< planar GBR 4:4:4 36bpp, big-endian
AV_PIX_FMT_GBRP12LE, ///< planar GBR 4:4:4 36bpp, little-endian
AV_PIX_FMT_GBRP14BE, ///< planar GBR 4:4:4 42bpp, big-endian
AV_PIX_FMT_GBRP14LE, ///< planar GBR 4:4:4 42bpp, little-endian
AV_PIX_FMT_YUVJ411P, ///< planar YUV 4:1:1, 12bpp, (1 Cr & Cb sample per 4x1 Y samples) full scale (JPEG), deprecated in favor of AV_PIX_FMT_YUV411P and setting color_range
AV_PIX_FMT_BAYER_BGGR8, ///< bayer, BGBG..(odd line), GRGR..(even line), 8-bit samples */
AV_PIX_FMT_BAYER_RGGB8, ///< bayer, RGRG..(odd line), GBGB..(even line), 8-bit samples */
AV_PIX_FMT_BAYER_GBRG8, ///< bayer, GBGB..(odd line), RGRG..(even line), 8-bit samples */
AV_PIX_FMT_BAYER_GRBG8, ///< bayer, GRGR..(odd line), BGBG..(even line), 8-bit samples */
AV_PIX_FMT_BAYER_BGGR16LE, ///< bayer, BGBG..(odd line), GRGR..(even line), 16-bit samples, little-endian */
AV_PIX_FMT_BAYER_BGGR16BE, ///< bayer, BGBG..(odd line), GRGR..(even line), 16-bit samples, big-endian */
AV_PIX_FMT_BAYER_RGGB16LE, ///< bayer, RGRG..(odd line), GBGB..(even line), 16-bit samples, little-endian */
AV_PIX_FMT_BAYER_RGGB16BE, ///< bayer, RGRG..(odd line), GBGB..(even line), 16-bit samples, big-endian */
AV_PIX_FMT_BAYER_GBRG16LE, ///< bayer, GBGB..(odd line), RGRG..(even line), 16-bit samples, little-endian */
AV_PIX_FMT_BAYER_GBRG16BE, ///< bayer, GBGB..(odd line), RGRG..(even line), 16-bit samples, big-endian */
AV_PIX_FMT_BAYER_GRBG16LE, ///< bayer, GRGR..(odd line), BGBG..(even line), 16-bit samples, little-endian */
AV_PIX_FMT_BAYER_GRBG16BE, ///< bayer, GRGR..(odd line), BGBG..(even line), 16-bit samples, big-endian */
AV_PIX_FMT_XVMC,///< XVideo Motion Acceleration via common packet passing
AV_PIX_FMT_YUV440P10LE, ///< planar YUV 4:4:0,20bpp, (1 Cr & Cb sample per 1x2 Y samples), little-endian
AV_PIX_FMT_YUV440P10BE, ///< planar YUV 4:4:0,20bpp, (1 Cr & Cb sample per 1x2 Y samples), big-endian
AV_PIX_FMT_YUV440P12LE, ///< planar YUV 4:4:0,24bpp, (1 Cr & Cb sample per 1x2 Y samples), little-endian
AV_PIX_FMT_YUV440P12BE, ///< planar YUV 4:4:0,24bpp, (1 Cr & Cb sample per 1x2 Y samples), big-endian
AV_PIX_FMT_AYUV64LE, ///< packed AYUV 4:4:4,64bpp (1 Cr & Cb sample per 1x1 Y & A samples), little-endian
AV_PIX_FMT_AYUV64BE, ///< packed AYUV 4:4:4,64bpp (1 Cr & Cb sample per 1x1 Y & A samples), big-endian
AV_PIX_FMT_VIDEOTOOLBOX, ///< hardware decoding through Videotoolbox
AV_PIX_FMT_P010LE, ///< like NV12, with 10bpp per component, data in the high bits, zeros in the low bits, little-endian
AV_PIX_FMT_P010BE, ///< like NV12, with 10bpp per component, data in the high bits, zeros in the low bits, big-endian
AV_PIX_FMT_GBRAP12BE, ///< planar GBR 4:4:4:4 48bpp, big-endian
AV_PIX_FMT_GBRAP12LE, ///< planar GBR 4:4:4:4 48bpp, little-endian
AV_PIX_FMT_GBRAP10BE, ///< planar GBR 4:4:4:4 40bpp, big-endian
AV_PIX_FMT_GBRAP10LE, ///< planar GBR 4:4:4:4 40bpp, little-endian
AV_PIX_FMT_MEDIACODEC, ///< hardware decoding through MediaCodec
AV_PIX_FMT_GRAY12BE, ///< Y , 12bpp, big-endian
AV_PIX_FMT_GRAY12LE, ///< Y , 12bpp, little-endian
AV_PIX_FMT_GRAY10BE, ///< Y , 10bpp, big-endian
AV_PIX_FMT_GRAY10LE, ///< Y , 10bpp, little-endian
AV_PIX_FMT_P016LE, ///< like NV12, with 16bpp per component, little-endian
AV_PIX_FMT_P016BE, ///< like NV12, with 16bpp per component, big-endian
/**
* Hardware surfaces for Direct3D11.
*
* This is preferred over the legacy AV_PIX_FMT_D3D11VA_VLD. The new D3D11
* hwaccel API and filtering support AV_PIX_FMT_D3D11 only.
*
* data[0] contains a ID3D11Texture2D pointer, and data[1] contains the
* texture array index of the frame as intptr_t if the ID3D11Texture2D is
* an array texture (or always 0 if it's a normal texture).
*/
AV_PIX_FMT_D3D11,
AV_PIX_FMT_GRAY9BE, ///< Y , 9bpp, big-endian
AV_PIX_FMT_GRAY9LE, ///< Y , 9bpp, little-endian
AV_PIX_FMT_GBRPF32BE, ///< IEEE-754 single precision planar GBR 4:4:4, 96bpp, big-endian
AV_PIX_FMT_GBRPF32LE, ///< IEEE-754 single precision planar GBR 4:4:4, 96bpp, little-endian
AV_PIX_FMT_GBRAPF32BE, ///< IEEE-754 single precision planar GBRA 4:4:4:4, 128bpp, big-endian
AV_PIX_FMT_GBRAPF32LE, ///< IEEE-754 single precision planar GBRA 4:4:4:4, 128bpp, little-endian
/**
* DRM-managed buffers exposed through PRIME buffer sharing.
*
* data[0] points to an AVDRMFrameDescriptor.
*/
AV_PIX_FMT_DRM_PRIME,
/**
* Hardware surfaces for OpenCL.
*
* data[i] contain 2D image objects (typed in C as cl_mem, used
* in OpenCL as image2d_t) for each plane of the surface.
*/
AV_PIX_FMT_OPENCL,
AV_PIX_FMT_GRAY14BE, ///< Y , 14bpp, big-endian
AV_PIX_FMT_GRAY14LE, ///< Y , 14bpp, little-endian
AV_PIX_FMT_GRAYF32BE, ///< IEEE-754 single precision Y, 32bpp, big-endian
AV_PIX_FMT_GRAYF32LE, ///< IEEE-754 single precision Y, 32bpp, little-endian
AV_PIX_FMT_YUVA422P12BE, ///< planar YUV 4:2:2,24bpp, (1 Cr & Cb sample per 2x1 Y samples), 12b alpha, big-endian
AV_PIX_FMT_YUVA422P12LE, ///< planar YUV 4:2:2,24bpp, (1 Cr & Cb sample per 2x1 Y samples), 12b alpha, little-endian
AV_PIX_FMT_YUVA444P12BE, ///< planar YUV 4:4:4,36bpp, (1 Cr & Cb sample per 1x1 Y samples), 12b alpha, big-endian
AV_PIX_FMT_YUVA444P12LE, ///< planar YUV 4:4:4,36bpp, (1 Cr & Cb sample per 1x1 Y samples), 12b alpha, little-endian
AV_PIX_FMT_NV24, ///< planar YUV 4:4:4, 24bpp, 1 plane for Y and 1 plane for the UV components, which are interleaved (first byte U and the following byte V)
AV_PIX_FMT_NV42, ///< as above, but U and V bytes are swapped
AV_PIX_FMT_NB ///< number of pixel formats, DO NOT USE THIS if you want to link with shared libav* because the number of formats might differ between versions
}
///
/// ffmpeg中AVFrame結構體的前半部分，因為它太長了我不需要完全移植過來
///
[StructLayout(LayoutKind.Sequential, Pack = 1, Size = 408)]
public struct AVFrame
{
//#define AV_NUM_DATA_POINTERS 8
// uint8_t* data[AV_NUM_DATA_POINTERS];
public IntPtr data1;// 一般是y分量
public IntPtr data2;// 一般是v分量
public IntPtr data3;// 一般是u分量
public IntPtr data4;// 一般是surface(dxva2硬解時)
public IntPtr data5;
public IntPtr data6;
public IntPtr data7;
public IntPtr data8;
public int linesize1;// y分量每行長度（stride)
public int linesize2;// v分量每行長度（stride)
public int linesize3;// u分量每行長度（stride)
public int linesize4;
public int linesize5;
public int linesize6;
public int linesize7;
public int linesize8;
//uint8_t **extended_data;
IntPtr extended_data;
public int width;
public int height;
public int nb_samples;
public AVPixelFormat format;
}
[StructLayout(LayoutKind.Sequential, Pack = 1, Size = 128)]
public struct AVCodec { }
[StructLayout(LayoutKind.Sequential, Pack = 1, Size = 72)]
public unsafe struct AVPacket
{
fixed byte frontUnused[24]; // 前部無關資料
public void* data;
public int size;
}
[StructLayout(LayoutKind.Sequential, Pack = 1, Size = 12)]
public struct AVBufferRef { }
[StructLayout(LayoutKind.Sequential, Pack = 1, Size = 904)]
public unsafe struct AVCodecContext
{
fixed byte frontUnused[880]; // 前部無關資料
public AVBufferRef* hw_frames_ctx;
}
[StructLayout(LayoutKind.Sequential)]
public struct AVDictionary { }
public unsafe static class FFHelper
{
const string avcodec = "avcodec-58";
const string avutil = "avutil-56";
const CallingConvention callingConvention = CallingConvention.Cdecl;
[DllImport(avcodec, CallingConvention = callingConvention)]
public extern static void avcodec_register_all();
[DllImport(avcodec, CallingConvention = callingConvention)]
public extern static AVCodec* avcodec_find_decoder(AVCodecID id);
[DllImport(avcodec, CallingConvention = callingConvention)]
public extern static AVPacket* av_packet_alloc();
[DllImport(avcodec, CallingConvention = callingConvention)]
public extern static void av_init_packet(AVPacket* pkt);
//[DllImport(avcodec, CallingConvention = callingConvention)]
//public extern static void av_packet_unref(AVPacket* pkt);
[DllImport(avcodec, CallingConvention = callingConvention)]
public extern static void av_packet_free(AVPacket** pkt);
[DllImport(avcodec, CallingConvention = callingConvention)]
public extern static AVCodecContext* avcodec_alloc_context3(AVCodec* codec);
[DllImport(avcodec, CallingConvention = callingConvention)]
public extern static int avcodec_open2(AVCodecContext* avctx, AVCodec* codec, AVDictionary** options);
//[DllImport(avcodec, CallingConvention = callingConvention)]
//public extern static int avcodec_decode_video2(IntPtr avctx, IntPtr picture, ref int got_picture_ptr, IntPtr avpkt);
[DllImport(avcodec, CallingConvention = callingConvention)]
public extern static void avcodec_free_context(AVCodecContext** avctx);
[DllImport(avcodec, CallingConvention = callingConvention)]
public extern static int avcodec_send_packet(AVCodecContext* avctx, AVPacket* pkt);
[DllImport(avcodec, CallingConvention = callingConvention)]
public extern static int avcodec_receive_frame(AVCodecContext* avctx, AVFrame* frame);
[DllImport(avutil, CallingConvention = callingConvention)]
public extern static int av_hwdevice_ctx_create(AVBufferRef** device_ctx, AVHWDeviceType type, string device, AVDictionary* opts, int flags);
[DllImport(avutil, CallingConvention = callingConvention)]
public extern static AVBufferRef* av_buffer_ref(AVBufferRef* buf);
[DllImport(avutil, CallingConvention = callingConvention)]
public extern static void av_buffer_unref(AVBufferRef** buf);
[DllImport(avutil, CallingConvention = callingConvention)]
public extern static AVFrame* av_frame_alloc();
[DllImport(avutil, CallingConvention = callingConvention)]
public extern static void av_frame_free(AVFrame** frame);
[DllImport(avutil, CallingConvention = callingConvention)]
public extern static void av_log_set_level(int level);
[DllImport(avutil, CallingConvention = callingConvention)]
public extern static int av_dict_set_int(AVDictionary** pm, string key, long value, int flags);
[DllImport(avutil, CallingConvention = callingConvention)]
public extern static void av_dict_free(AVDictionary** m);
}
}
上文中主要有幾個地方是知識點，大家做c#的如果需要和底層互動可以瞭解一下
- 結構體的使用
結構體在c#與c/c++基本一致，都是記憶體連續變數的一種組合方式。與c/c++相同，在c#中，如果我們不知道（或者可以規避，因為結構體可能很複雜，很多無關欄位）結構體細節只知道結構體整體大小時，我們可以用Pack=1,SizeConst=來表示一個大小已知的結構體。 - 指標的使用
c#中，有兩種儲存記憶體地址（指標）的方式，一是使用interop體系中的IntPtr型別（大家可以將其想象成void*）,一是在不安全的上下文（unsafe）中使用結構體型別指標（此處不討論c++類指標） - unsafe和fixed使用
簡單來說，有了unsafe你才能用指標；而有了fixed你才能確保指標指向位置不被GC壓縮。我們使用fixed達到的效果就是顯式跳過了結構體中前部無關資料（參考上文中AVCodecContext等結構體定義），後文中我們還會使用fixed。
現在我們開始編寫解碼和播放部分（即我們的具體應用）程式碼
FFPlayer.cs
using Microsoft.DirectX;
using Microsoft.DirectX.Direct3D;
using System;
using System.Drawing;
using System.Runtime.InteropServices;
using System.Text;
using System.Windows.Forms;
using static MultiPlayer.FFHelper;
namespace MultiPlayer
{
public unsafe partial class FFPlayer : UserControl
{
[DllImport("msvcrt", EntryPoint = "memcpy", CallingConvention = CallingConvention.Cdecl, SetLastError = false)]
static extern void memcpy(IntPtr dest, IntPtr src, int count); // 用於在解碼器和directx間拷貝記憶體的c函式
private IntPtr contentPanelHandle; // 畫面渲染的控制元件控制代碼，因為畫面渲染時可能出於非UI執行緒，因此先儲存控制代碼避免CLR報錯
private int lastIWidth, lastIHeight; // 上次控制元件大小，用於在控制元件大小改變時做出判定重新初始化渲染上下文
private Rectangle lastCBounds; // 臨時變數，儲存上次控制元件區域（螢幕座標）
private Rectangle lastVRect; // 臨時變數，儲存上次解碼出的影象大小
private Device device; // 當使用軟解時，這個變數生效，它是IDirect3Device9*物件，用於繪製YUV
private Surface surface; // 當使用軟解時，這個變數生效，它是IDirect3Surface9*物件，用於接受解碼後的YUV資料
AVPixelFormat lastFmt; // 上次解碼出的影象資料型別，這個理論上不會變
AVCodec* codec; // ffmpeg的解碼器
AVCodecContext* ctx; // ffmpeg的解碼上下文
AVBufferRef* hw_ctx; // ffmpeg的解碼器硬體加速上下文，作為ctx的擴充套件存在
AVPacket* avpkt; // ffmpeg的資料包，用於封送待解碼資料
IntPtr nalData; // 一塊預分配記憶體，作為avpkt中真正儲存資料的記憶體地址
AVFrame* frame; // ffmpeg的已解碼幀，用於回傳解碼後的影象
private volatile bool _released = false; // 資源釋放標識，與鎖配合使用避免重複釋放資源（由於底層是c/c++，多執行緒下double free會導致程式崩潰）
private object _codecLocker = new object(); // 鎖，用於多執行緒下的互斥
static FFPlayer()
{
avcodec_register_all(); // 靜態塊中註冊ffmpeg解碼器
}
public FFPlayer()
{
InitializeComponent();
// 過程中，下列物件只需初始化一次
frame = av_frame_alloc();
avpkt = av_packet_alloc();
av_init_packet(avpkt);
nalData = Marshal.AllocHGlobal(1024 * 1024);
codec = avcodec_find_decoder(AVCodecID.AV_CODEC_ID_H264);
avpkt->data = (void*)nalData;
}
~FFPlayer()
{
// 過程中，下列物件只需釋放一次
if (null != frame)
fixed (AVFrame** LPframe = &frame)
av_frame_free(LPframe);
if (null != avpkt)
fixed (AVPacket** LPpkt = &avpkt)
av_packet_free(LPpkt);
if (default != nalData)
Marshal.FreeHGlobal(nalData);
}
// 釋放資源
// 此函式並非表示“終止”，更多的是表示“改變”和“重置”，實際上對此函式的呼叫更多的是發生在介面大小發生變化時和網路掉包導致硬解異常時
private void Releases()
{
// 過程中，下列物件會重複建立和銷燬多次
lock (_codecLocker)
{
if (_released) return;
if (null != ctx)
fixed (AVCodecContext** LPctx = &ctx)
avcodec_free_context(LPctx);
if (null != hw_ctx)
fixed (AVBufferRef** LPhw_ctx = &hw_ctx)
av_buffer_unref(LPhw_ctx);
// (PS:device和surface我們將其置為null，讓GC幫我們呼叫Finalize，它則會自行釋放資源）
surface = null;
device = null;
lastFmt = AVPixelFormat.AV_PIX_FMT_NONE;
_released = true;
}
}
// Load事件中儲存控制元件控制代碼
private void FFPlayer_Load(object sender, EventArgs e)
{
contentPanelHandle = Handle; // 這個控制代碼也可以是你控制元件內真正要渲染畫面的控制代碼
lastCBounds = ClientRectangle; // 同理，區域也不一定是自身顯示區域
}
// 解碼函式，由外部呼叫，送一一個分片好的nal
public void H264Received(byte[] nal)
{
lock (_codecLocker)
{
// 判斷介面大小更改了，先重置一波
// (因為DirectX中介面大小改變是一件大事，沒得法繞過，只能推倒從來）
// 如果你的顯示控制元件不是當前控制元件本身，此處需要做修改
if (!ClientRectangle.Equals(lastCBounds))
{
lastCBounds = ClientRectangle;
Releases();
}
if (null == ctx)
{
// 第一次接收到待解碼資料時初始化一個解碼器上下文
ctx = avcodec_alloc_context3(codec);
if (null == ctx)
{
return;
}
// 通過引數傳遞控制元件控制代碼給硬體加速上下文
AVDictionary* dic;
av_dict_set_int(&dic, "hWnd", contentPanelHandle.ToInt64(), 0);
fixed (AVBufferRef** LPhw_ctx = &hw_ctx)
{
if (av_hwdevice_ctx_create(LPhw_ctx, AVHWDeviceType.AV_HWDEVICE_TYPE_DXVA2,
null, dic, 0) >= 0)
{
ctx->hw_frames_ctx = av_buffer_ref(hw_ctx);
}
}
av_dict_free(&dic);
ctx->hw_frames_ctx = av_buffer_ref(hw_ctx);
if (avcodec_open2(ctx, codec, null) < 0)
{
fixed (AVCodecContext** LPctx = &ctx)
avcodec_free_context(LPctx);
fixed (AVBufferRef** LPhw_ctx = &hw_ctx)
av_buffer_unref(LPhw_ctx);
return;
}
}
_released = false;
// 開始解碼
Marshal.Copy(nal, 0, nalData, nal.Length);
avpkt->size = nal.Length;
if (avcodec_send_packet(ctx, avpkt) < 0)
{
Releases(); return; // 如果程式走到了這裡，一般是因為網路掉包導致nal資料不連續，沒辦法， 推倒從來
}
receive_frame:
int err = avcodec_receive_frame(ctx, frame);
if (err == -11) return; // EAGAIN
if (err < 0)
{
Releases(); return; // 同上，一般這裡很少出錯，但一旦發生，只能推倒從來
}
// 嘗試播放一幀畫面
AVFrame s_frame = *frame;
// 這裡由於我無論如何都要加速，而一般顯示卡最相容的是yv12格式，因此我只對dxva2和420p做了處理，如果你的h264解出來不是這些，我建議轉成rgb（那你就需要編譯和使用swscale模組了）
if (s_frame.format != AVPixelFormat.AV_PIX_FMT_DXVA2_VLD && s_frame.format != AVPixelFormat.AV_PIX_FMT_YUV420P && s_frame.format != AVPixelFormat.AV_PIX_FMT_YUVJ420P) return;
try
{
int width = s_frame.width;
int height = s_frame.height;
if (lastIWidth != width || lastIHeight != height || lastFmt != s_frame.format) // 這個if判定的是第一次嘗試渲染，因為一般碼流的寬高和格式不會變
{
if (s_frame.format != AVPixelFormat.AV_PIX_FMT_DXVA2_VLD)
{
// 假如硬解不成功（例如h264是baseline的，ffmpeg新版不支援baseline的dxva2硬解）
// 我們就嘗試用directx渲染yuv，至少省去yuv轉rgb，可以略微節省一丟丟cpu
PresentParameters pp = new PresentParameters();
pp.Windowed = true;
pp.SwapEffect = SwapEffect.Discard;
pp.BackBufferCount = 0;
pp.DeviceWindowHandle = contentPanelHandle;
pp.BackBufferFormat = Manager.Adapters.Default.CurrentDisplayMode.Format;
pp.EnableAutoDepthStencil = false;
pp.PresentFlag = PresentFlag.Video;
pp.FullScreenRefreshRateInHz = 0;//D3DPRESENT_RATE_DEFAULT
pp.PresentationInterval = 0;//D3DPRESENT_INTERVAL_DEFAULT
Caps caps = Manager.GetDeviceCaps(Manager.Adapters.Default.Adapter, DeviceType.Hardware);
CreateFlags behaviorFlas = CreateFlags.MultiThreaded | CreateFlags.FpuPreserve;
if (caps.DeviceCaps.SupportsHardwareTransformAndLight)
{
behaviorFlas |= CreateFlags.HardwareVertexProcessing;
}
else
{
behaviorFlas |= CreateFlags.SoftwareVertexProcessing;
}
device = new Device(Manager.Adapters.Default.Adapter, DeviceType.Hardware, contentPanelHandle, behaviorFlas, pp);
//(Format)842094158;//nv12
surface = device.CreateOffscreenPlainSurface(width, height, (Format)842094169, Pool.Default);//yv12，顯示卡相容性最好的格式
}
lastIWidth = width;
lastIHeight = height;
lastVRect = new Rectangle(0, 0, lastIWidth, lastIHeight);
lastFmt = s_frame.format;
}
if (lastFmt != AVPixelFormat.AV_PIX_FMT_DXVA2_VLD)
{
// 如果硬解失敗，我們還需要把yuv拷貝到surface
//ffmpeg沒有yv12，只有i420，而一般顯示卡又支援的是yv12，因此下文中uv分量是反向的
int stride;
var gs = surface.LockRectangle(LockFlags.DoNotWait, out stride);
if (gs == null) return;
for (int i = 0; i < lastIHeight; i++)
{
memcpy(gs.InternalData + i * stride, s_frame.data1 + i * s_frame.linesize1, lastIWidth);
}
for (int i = 0; i < lastIHeight / 2; i++)
{
memcpy(gs.InternalData + stride * lastIHeight + i * stride / 2, s_frame.data3 + i * s_frame.linesize3, lastIWidth / 2);
}
for (int i = 0; i < lastIHeight / 2; i++)
{
memcpy(gs.InternalData + stride * lastIHeight + stride * lastIHeight / 4 + i * stride / 2, s_frame.data2 + i * s_frame.linesize2, lastIWidth / 2);
}
surface.UnlockRectangle();
}