音视频-SDL播放YUV（上）

音视频-SDL播放BMP

自己造一张YUV格式的图片

jpg源文件

将JPG图片格式转为YUV

PS G:\Resource> ffmpeg -i .\in.jpg -pix_fmt yuv420p .\out_yuv420p.yuv

ffmpeg version 4.3.2 Copyright (c) 2000-2021 the FFmpeg developers
  built with gcc 10.2.0 (Rev6, Built by MSYS2 project)
  configuration: --prefix=/usr/local/ffmpeg --enable-shared --disable-static --enable-gpl --enable-nonfree --enable-libfdk-aac --enable-libx264
  libavutil      56. 51.100 / 56. 51.100
  libavcodec     58. 91.100 / 58. 91.100
  libavformat    58. 45.100 / 58. 45.100
  libavdevice    58. 10.100 / 58. 10.100
  libavfilter     7. 85.100 /  7. 85.100
  libswscale      5.  7.100 /  5.  7.100
  libswresample   3.  7.100 /  3.  7.100
  libpostproc    55.  7.100 / 55.  7.100
Input #0, image2, from '.\in.jpg':
  Duration: 00:00:00.04, start: 0.000000, bitrate: 20505 kb/s
    Stream #0:0: Video: mjpeg (Baseline), yuvj420p(pc, bt470bg/unknown/unknown), 512x512 [SAR 192:192 DAR 1:1], 25 tbr, 25 tbn, 25 tbc
Stream mapping:
  Stream #0:0 -> #0:0 (mjpeg (native) -> rawvideo (native))
Press [q] to stop, [?] for help
[swscaler @ 0000000002b1f000] deprecated pixel format used, make sure you did set range correctly
Output #0, rawvideo, to '.\out_yuv420p.yuv':
  Metadata:
    encoder         : Lavf58.45.100
    Stream #0:0: Video: rawvideo (I420 / 0x30323449), yuv420p, 512x512 [SAR 1:1 DAR 1:1], q=2-31, 78643 kb/s, 25 fps, 25 tbn, 25 tbc
    Metadata:
      encoder         : Lavc58.91.100 rawvideo
frame=    1 fps=0.0 q=-0.0 Lsize=     384kB time=00:00:00.04 bitrate=78643.2kbits/s speed=2.11x
video:384kB audio:0kB subtitle:0kB other streams:0kB global headers:0kB muxing overhead: 0.000000%

主要信息 yuv420p, 512x512

image.png

使用FFmpeg播放YUV格式文件

ffplay -i .\out_yuv420p.yuv -pix_fmt yuv420p -s 512x512

image.png

ps : 终端拉长了，为了截图，正常输出是512x512

YUV数据有了， 使用SDL播放YUV

---

---

SDL播放YUV和 播放BMP思路差不多，差别在于传入的文件格式内容, 纹理的处理不同

/**
 *  \brief Create a texture for a rendering context.
 *
 *  \param renderer The renderer.
 *  \param format The format of the texture.
 *  \param access One of the enumerated values in ::SDL_TextureAccess.
 *  \param w      The width of the texture in pixels.
 *  \param h      The height of the texture in pixels.
 *
 *  \return The created texture is returned, or NULL if no rendering context was
 *          active,  the format was unsupported, or the width or height were out
 *          of range.
 *
 *  \note The contents of the texture are not defined at creation.
 *
 *  \sa SDL_QueryTexture()
 *  \sa SDL_UpdateTexture()
 *  \sa SDL_DestroyTexture()
 */
extern DECLSPEC SDL_Texture * SDLCALL SDL_CreateTexture(SDL_Renderer * renderer,
                                                        Uint32 format,
                                                        int access, int w,
                                                        int h);

关于SDL_TextureAccess

/**
 *  \brief The access pattern allowed for a texture.
 */
typedef enum
{
    SDL_TEXTUREACCESS_STATIC,    /**< Changes rarely, not lockable */
    SDL_TEXTUREACCESS_STREAMING, /**< Changes frequently, lockable */
    SDL_TEXTUREACCESS_TARGET     /**< Texture can be used as a render target */
} SDL_TextureAccess;

关于SDL_PixelFormatEnum

/* Note: If you modify this list, update SDL_GetPixelFormatName() */
typedef enum
{
    SDL_PIXELFORMAT_UNKNOWN,
    SDL_PIXELFORMAT_INDEX1LSB =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_INDEX1, SDL_BITMAPORDER_4321, 0,
                               1, 0),
    SDL_PIXELFORMAT_INDEX1MSB =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_INDEX1, SDL_BITMAPORDER_1234, 0,
                               1, 0),
    SDL_PIXELFORMAT_INDEX4LSB =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_INDEX4, SDL_BITMAPORDER_4321, 0,
                               4, 0),
    SDL_PIXELFORMAT_INDEX4MSB =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_INDEX4, SDL_BITMAPORDER_1234, 0,
                               4, 0),
    SDL_PIXELFORMAT_INDEX8 =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_INDEX8, 0, 0, 8, 1),
    SDL_PIXELFORMAT_RGB332 =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_PACKED8, SDL_PACKEDORDER_XRGB,
                               SDL_PACKEDLAYOUT_332, 8, 1),
    SDL_PIXELFORMAT_XRGB4444 =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_PACKED16, SDL_PACKEDORDER_XRGB,
                               SDL_PACKEDLAYOUT_4444, 12, 2),
    SDL_PIXELFORMAT_RGB444 = SDL_PIXELFORMAT_XRGB4444,
    SDL_PIXELFORMAT_XBGR4444 =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_PACKED16, SDL_PACKEDORDER_XBGR,
                               SDL_PACKEDLAYOUT_4444, 12, 2),
    SDL_PIXELFORMAT_BGR444 = SDL_PIXELFORMAT_XBGR4444,
    SDL_PIXELFORMAT_XRGB1555 =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_PACKED16, SDL_PACKEDORDER_XRGB,
                               SDL_PACKEDLAYOUT_1555, 15, 2),
    SDL_PIXELFORMAT_RGB555 = SDL_PIXELFORMAT_XRGB1555,
    SDL_PIXELFORMAT_XBGR1555 =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_PACKED16, SDL_PACKEDORDER_XBGR,
                               SDL_PACKEDLAYOUT_1555, 15, 2),
    SDL_PIXELFORMAT_BGR555 = SDL_PIXELFORMAT_XBGR1555,
    SDL_PIXELFORMAT_ARGB4444 =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_PACKED16, SDL_PACKEDORDER_ARGB,
                               SDL_PACKEDLAYOUT_4444, 16, 2),
    SDL_PIXELFORMAT_RGBA4444 =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_PACKED16, SDL_PACKEDORDER_RGBA,
                               SDL_PACKEDLAYOUT_4444, 16, 2),
    SDL_PIXELFORMAT_ABGR4444 =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_PACKED16, SDL_PACKEDORDER_ABGR,
                               SDL_PACKEDLAYOUT_4444, 16, 2),
    SDL_PIXELFORMAT_BGRA4444 =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_PACKED16, SDL_PACKEDORDER_BGRA,
                               SDL_PACKEDLAYOUT_4444, 16, 2),
    SDL_PIXELFORMAT_ARGB1555 =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_PACKED16, SDL_PACKEDORDER_ARGB,
                               SDL_PACKEDLAYOUT_1555, 16, 2),
    SDL_PIXELFORMAT_RGBA5551 =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_PACKED16, SDL_PACKEDORDER_RGBA,
                               SDL_PACKEDLAYOUT_5551, 16, 2),
    SDL_PIXELFORMAT_ABGR1555 =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_PACKED16, SDL_PACKEDORDER_ABGR,
                               SDL_PACKEDLAYOUT_1555, 16, 2),
    SDL_PIXELFORMAT_BGRA5551 =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_PACKED16, SDL_PACKEDORDER_BGRA,
                               SDL_PACKEDLAYOUT_5551, 16, 2),
    SDL_PIXELFORMAT_RGB565 =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_PACKED16, SDL_PACKEDORDER_XRGB,
                               SDL_PACKEDLAYOUT_565, 16, 2),
    SDL_PIXELFORMAT_BGR565 =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_PACKED16, SDL_PACKEDORDER_XBGR,
                               SDL_PACKEDLAYOUT_565, 16, 2),
    SDL_PIXELFORMAT_RGB24 =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_ARRAYU8, SDL_ARRAYORDER_RGB, 0,
                               24, 3),
    SDL_PIXELFORMAT_BGR24 =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_ARRAYU8, SDL_ARRAYORDER_BGR, 0,
                               24, 3),
    SDL_PIXELFORMAT_XRGB8888 =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_PACKED32, SDL_PACKEDORDER_XRGB,
                               SDL_PACKEDLAYOUT_8888, 24, 4),
    SDL_PIXELFORMAT_RGB888 = SDL_PIXELFORMAT_XRGB8888,
    SDL_PIXELFORMAT_RGBX8888 =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_PACKED32, SDL_PACKEDORDER_RGBX,
                               SDL_PACKEDLAYOUT_8888, 24, 4),
    SDL_PIXELFORMAT_XBGR8888 =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_PACKED32, SDL_PACKEDORDER_XBGR,
                               SDL_PACKEDLAYOUT_8888, 24, 4),
    SDL_PIXELFORMAT_BGR888 = SDL_PIXELFORMAT_XBGR8888,
    SDL_PIXELFORMAT_BGRX8888 =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_PACKED32, SDL_PACKEDORDER_BGRX,
                               SDL_PACKEDLAYOUT_8888, 24, 4),
    SDL_PIXELFORMAT_ARGB8888 =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_PACKED32, SDL_PACKEDORDER_ARGB,
                               SDL_PACKEDLAYOUT_8888, 32, 4),
    SDL_PIXELFORMAT_RGBA8888 =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_PACKED32, SDL_PACKEDORDER_RGBA,
                               SDL_PACKEDLAYOUT_8888, 32, 4),
    SDL_PIXELFORMAT_ABGR8888 =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_PACKED32, SDL_PACKEDORDER_ABGR,
                               SDL_PACKEDLAYOUT_8888, 32, 4),
    SDL_PIXELFORMAT_BGRA8888 =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_PACKED32, SDL_PACKEDORDER_BGRA,
                               SDL_PACKEDLAYOUT_8888, 32, 4),
    SDL_PIXELFORMAT_ARGB2101010 =
        SDL_DEFINE_PIXELFORMAT(SDL_PIXELTYPE_PACKED32, SDL_PACKEDORDER_ARGB,
                               SDL_PACKEDLAYOUT_2101010, 32, 4),

    /* Aliases for RGBA byte arrays of color data, for the current platform */
#if SDL_BYTEORDER == SDL_BIG_ENDIAN
    SDL_PIXELFORMAT_RGBA32 = SDL_PIXELFORMAT_RGBA8888,
    SDL_PIXELFORMAT_ARGB32 = SDL_PIXELFORMAT_ARGB8888,
    SDL_PIXELFORMAT_BGRA32 = SDL_PIXELFORMAT_BGRA8888,
    SDL_PIXELFORMAT_ABGR32 = SDL_PIXELFORMAT_ABGR8888,
#else
    SDL_PIXELFORMAT_RGBA32 = SDL_PIXELFORMAT_ABGR8888,
    SDL_PIXELFORMAT_ARGB32 = SDL_PIXELFORMAT_BGRA8888,
    SDL_PIXELFORMAT_BGRA32 = SDL_PIXELFORMAT_ARGB8888,
    SDL_PIXELFORMAT_ABGR32 = SDL_PIXELFORMAT_RGBA8888,
#endif

    SDL_PIXELFORMAT_YV12 =      /**< Planar mode: Y + V + U  (3 planes) */
        SDL_DEFINE_PIXELFOURCC('Y', 'V', '1', '2'),
    SDL_PIXELFORMAT_IYUV =      /**< Planar mode: Y + U + V  (3 planes) */
        SDL_DEFINE_PIXELFOURCC('I', 'Y', 'U', 'V'),
    SDL_PIXELFORMAT_YUY2 =      /**< Packed mode: Y0+U0+Y1+V0 (1 plane) */
        SDL_DEFINE_PIXELFOURCC('Y', 'U', 'Y', '2'),
    SDL_PIXELFORMAT_UYVY =      /**< Packed mode: U0+Y0+V0+Y1 (1 plane) */
        SDL_DEFINE_PIXELFOURCC('U', 'Y', 'V', 'Y'),
    SDL_PIXELFORMAT_YVYU =      /**< Packed mode: Y0+V0+Y1+U0 (1 plane) */
        SDL_DEFINE_PIXELFOURCC('Y', 'V', 'Y', 'U'),
    SDL_PIXELFORMAT_NV12 =      /**< Planar mode: Y + U/V interleaved  (2 planes) */
        SDL_DEFINE_PIXELFOURCC('N', 'V', '1', '2'),
    SDL_PIXELFORMAT_NV21 =      /**< Planar mode: Y + V/U interleaved  (2 planes) */
        SDL_DEFINE_PIXELFOURCC('N', 'V', '2', '1'),
    SDL_PIXELFORMAT_EXTERNAL_OES =      /**< Android video texture format */
        SDL_DEFINE_PIXELFOURCC('O', 'E', 'S', ' ')
} SDL_PixelFormatEnum;

刚刚转出来的是yuv420p的格式。 用的是IYUV

跟播放BMP的不一样的地方是纹理的加载方式， 因为目前读取的是源文件， 所以用QFile打开文件，读取文件数据, 更新到render中

    // 贴图纹理
    texture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_IYUV, SDL_TEXTUREACCESS_STREAMING, IMG_W, IMG_H);
    END(!texture, SDL_CreateTextureFromSurface);

    // YUV420p ==> yyyyuu
    qDebug() << "texture" << texture;

    // 打开文件
    openRet = infile.open(QFile::ReadOnly);
    END(!openRet, infile.open);
    qDebug() << "openRet" << openRet;

    // 将YUV数据更新到render中
    renderUpdateRet = SDL_UpdateTexture(texture, nullptr, infile.readAll().data(), IMG_W);
    END(renderUpdateRet, SDL_RenderCopy);

    // 拷贝纹理数据到渲染目标（默认是window）
    renderCopyRet = SDL_RenderCopy(renderer, texture, nullptr, nullptr);
    END(renderCopyRet, SDL_RenderCopy);

---

---

实现

#include "playthread.h"
#include 
#include 

extern "C" {
#include 
}


#define FILENAME "G:/Resource/out_yuv420p.yuv"
#define IMG_W 512
#define IMG_H 512


// 出错了就执行goto end
#define END(judge, func) \
    if (judge) { \
        qDebug() << #func << "Error" << SDL_GetError(); \
        goto end; \
    }


Playthread::Playthread(QObject *parent) : QThread(parent) {
    // 创建信号连接
    connect(this, &Playthread::finished,
            this, &Playthread::deleteLater);
}

Playthread::~Playthread() {
    // 断开所有的连接
    disconnect();
    // 内存回收之前，正常结束线程
    requestInterruption();
    // 安全退出
    quit();
    wait();
    qDebug() << this << "Playthread 析构（内存被回收）";
}



void Playthread::run() {
    if(SDL_Init(SDL_INIT_VIDEO)) {
        qDebug() << "SDL_Init error : " << SDL_GetError();
        return;
    }

    // 创建一个SDL Window窗口
    SDL_Window *window = nullptr;
    // 像素数据
    SDL_Surface *surface = nullptr;
    // 纹理（直接跟特定驱动程序相关的像素数据）
    SDL_Texture *texture = nullptr;
    // 渲染上下文
    SDL_Renderer *renderer = nullptr;

    int renderUpdateRet;
    int renderCopyRet;
    int openRet;

    //YUV文件输入
    QFile infile(FILENAME);

    window = SDL_CreateWindow("SDL播放BMP",
                              100, 100,
                              600, 600,
                              SDL_WINDOW_SHOWN);
    END(!window, SDL_CreateWindow);


    renderer = SDL_CreateRenderer(window, -1,  SDL_RENDERER_ACCELERATED | SDL_RENDERER_PRESENTVSYNC);
    if (!renderer) { // 说明开启硬件加速失败
        renderer = SDL_CreateRenderer(window, -1, 0);
    }
    END(!renderer, SDL_CreateRenderer);


    // 贴图纹理
    texture = SDL_CreateTexture(renderer, SDL_PIXELFORMAT_IYUV, SDL_TEXTUREACCESS_STREAMING, IMG_W, IMG_H);
    END(!texture, SDL_CreateTextureFromSurface);

    // YUV420p ==> yyyyuu
    qDebug() << "texture" << texture;

    // 打开文件
    openRet = infile.open(QFile::ReadOnly);
    END(!openRet, infile.open);
    qDebug() << "openRet" << openRet;

    // 将YUV数据更新到render中
    renderUpdateRet = SDL_UpdateTexture(texture, nullptr, infile.readAll().data(), IMG_W);
    END(renderUpdateRet, SDL_RenderCopy);

    // 拷贝纹理数据到渲染目标（默认是window）
    renderCopyRet = SDL_RenderCopy(renderer, texture, nullptr, nullptr);
    END(renderCopyRet, SDL_RenderCopy);

    // 将此前的所有需要渲染的内容更新到屏幕上
    SDL_RenderPresent(renderer);

    // 延迟3秒退出
    SDL_Delay(3000);

end:


    SDL_DestroyWindow(window);
    SDL_FreeSurface(surface);
    SDL_DestroyTexture(texture);
    SDL_DestroyRenderer(renderer);
    // 清除所有子系统
    SDL_Quit();
}

void Playthread::setStop(bool stop) {
    _stop = stop;
}

image.png

---

---

播放YUV视频

和播放图片差不多，核心处理的代码 ， 将一帧的数据渲染到屏幕上，现在这里是播放yuv,输入的帧率，1s多少帧的填充刷新，我们现在是读取文件的内容传入

下载一个自己的YUV数据流， 或者自己录制一个
下载地址 ：http://trace.eas.asu.edu/yuv/index.html
视频内容 ： Big Buck Bunny
像素格式 ：yuv420p
分辨率 ：352X288
帧率 ：24

核心代码

    // 打开文件
    openRet = infile.open(QFile::ReadOnly);
    END(!openRet, infile.open);
    qDebug() << "openRet" << openRet;


    while(infile.read(data, imgSize) > 0) {
        // 将YUV数据更新到render中
        renderUpdateRet = SDL_UpdateTexture(texture, nullptr, data, IMG_W);
        END(renderUpdateRet, SDL_RenderCopy);

        // 拷贝纹理数据到渲染目标（默认是window）
        renderCopyRet = SDL_RenderCopy(renderer, texture, nullptr, nullptr);
        END(renderCopyRet, SDL_RenderCopy);

        // 将此前的所有需要渲染的内容更新到屏幕上
        SDL_RenderPresent(renderer);
    }

播放YUV流