Question

我正在ffmpeg库中使用带有RGB24或ARGB像素格式的QTRLE格式创建视频。但是没有播放视频。
但是我使用的是带有yuv格式的H264格式，那么它的工作正常。

ffmpeg不支持QTRLE，或者我有任何错误吗？

static void video_encode_example(const char *filename, int codec_id)
{
        AVCodec *codec;
        AVCodecContext *c = NULL;
        int i, ret, x, y, got_output;
        FILE *f;
        AVFrame *frame;
        AVPacket pkt;
        uint8_t endcode[] = { 0, 0, 1, 0xb7 };

        printf("Encode video file %s\n", filename);

        /* find the mpeg1 video encoder */

        codec = avcodec_find_encoder((AVCodecID) codec_id);
        //  codec = 28;
        if (!codec) {
            fprintf(stderr, "Codec not found : %d\n", codec_id);
            exit(1);
        }

        c = avcodec_alloc_context3(codec);

        if (!c) {
            fprintf(stderr, "Could not allocate video codec context\n");
            exit(1);
        }

        /* put sample parameters */
        c->bit_rate = 400000;
        /* resolution must be a multiple of two */
        c->width = 352;
        c->height = 288;
        /* frames per second */
        c->time_base = (AVRational ) { 1, 25 };
        /* emit one intra frame every ten frames
         * check frame pict_type before passing frame
         * to encoder, if frame->pict_type is AV_PICTURE_TYPE_I
         * then gop_size is ignored and the output of encoder
         * will always be I frame irrespective to gop_size
         */
        c->gop_size = 10;
        c->max_b_frames = 1;
        c->pix_fmt = AV_PIX_FMT_RGB24;

        if (codec_id == AV_CODEC_ID_H264)
            av_opt_set(c->priv_data, "preset", "slow", 0);

        /* open it */
        if (avcodec_open2(c, codec, NULL) < 0) {
            fprintf(stderr, "Could not open codec\n");
            exit(1);
        }

        f = fopen(filename, "wb");
        if (!f) {
            fprintf(stderr, "Could not open %s\n", filename);
            exit(1);
        }

        frame = av_frame_alloc();
        if (!frame) {
            fprintf(stderr, "Could not allocate video frame\n");
            exit(1);
        }
        frame->format = c->pix_fmt;
        frame->width = c->width;
        frame->height = c->height;

        /* the image can be allocated by any means and av_image_alloc() is
         * just the most convenient way if av_malloc() is to be used */
        ret = av_image_alloc(frame->data, frame->linesize, c->width, c->height,
                c->pix_fmt, 32);
        if (ret < 0) {
            fprintf(stderr, "Could not allocate raw picture buffer\n");
            exit(1);
        }
        ////////////////////////////////////
        cv::Mat input = imread("image for creating video(image.png)");
        Mat output;
        resize(input, input, Size(c->width, c->height));
        cvtColor(input, input, CV_BGR2RGB);

        av_image_fill_arrays(frame->data, frame->linesize, input.data,
                c->pix_fmt, c->width, c->height, 1);

        ////////////////////////////////////

        for (i = 0; i < 250; i++) {
            av_init_packet(&pkt);
            pkt.data = NULL;    // packet data will be allocated by the encoder
            pkt.size = 0;

            fflush(stdout);

            frame->pts = i;

            /* encode the image */
            ret = avcodec_encode_video2(c, &pkt, frame, &got_output);
            if (ret < 0) {
                fprintf(stderr, "Error encoding frame\n");
                exit(1);
            }

            if (got_output) {
                printf("Write frame %3d (size=%5d)\n", i, pkt.size);
                fwrite(pkt.data, 1, pkt.size, f);
                av_packet_unref(&pkt);
            }
        }

        /* get the delayed frames */
        for (got_output = 1; got_output; i++) {
            fflush(stdout);

            ret = avcodec_encode_video2(c, &pkt, NULL, &got_output);
            if (ret < 0) {
                fprintf(stderr, "Error encoding frame\n");
                exit(1);
            }

            if (got_output) {
                printf("Write frame %3d (size=%5d)\n", i, pkt.size);
                fwrite(pkt.data, 1, pkt.size, f);
                av_packet_unref(&pkt);
            }
        }

        /* add sequence end code to have a real mpeg file */
        fwrite(endcode, 1, sizeof(endcode), f);
        fclose(f);

        avcodec_close(c);
        av_free(c);
    //  av_freep(&frame->data[0]);
        av_frame_free(&frame);
        printf("\n");
}

int main() {
    av_register_all();
    video_encode_example("test.mov", AV_CODEC_ID_QTRLE);
}

Answer 1

FFmpeg支持QTRLE，问题是您正在查看错误的示例。

您提供的代码似乎基于from sqlalchemy.orm.session import make_transient def clone_agent(id): s = app.db.session agent = s.query(Agent).get(id) c = None # you need get child before expunge agent, otherwise the children will be empty if agent.campaigns: c = agent.campaigns[0] s.expunge(c) make_transient(c) c.id = None s.expunge(agent) agent.id = None # I have unique constraint on the following column. agent.name = agent.name + '_clone' agent.externalId = - agent.externalId # find a number that not in db. make_transient(agent) s.add(agent) s.commit() # commit so the agent will save to database and get an id if c: assert agent.id c.agent_id = agent.id # attatch child to parent. agent_id is a foreign key s.add(c) s.commit()，karma start使用的示例仅适用于编解码器。它只输出原始decoding_encoding.c或libavcodec。

如果要创建h264文件，则必须使用mpg以此格式复用结果。请改为查看mov示例。

QTRLE是否受ffmpeg支持？

1 个答案: