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    13 mai 2011, par

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  • Cropping Square Video using FFmpeg

    27 juin 2014, par zoruc

    Updated

    So I am trying to decode a mp4 file, crop the video into a square, and then re encode it back out to another mp4 file. This is my current code but there are a few issues with it.

    One is that the video doesn’t keep its rotation after the video has been re encoded

    Second is that the frames get outputted in a very fast video file that is not the same length as the original

    Third is that there is no sound

    Lastly and most importantly is do I need AVFilter to do the frame cropping or can it just be done per frame as a resize of the frame and then encoded back out.

    const char *inputPath = "test.mp4";
    const char *outPath = "cropped.mp4";
    const char *outFileType = "mp4";

    static AVFrame *oframe = NULL;
    static AVFilterGraph *filterGraph = NULL;  
    static AVFilterContext *crop_ctx = NULL;
    static AVFilterContext *buffersink_ctx = NULL;
    static AVFilterContext *buffer_ctx = NULL;

    int err;

    int crop_video(int width, int height) {

    av_register_all();
    avcodec_register_all();
    avfilter_register_all();

    AVFormatContext *inCtx = NULL;

    // open input file
    err = avformat_open_input(&inCtx, inputPath, NULL, NULL);
    if (err < 0) {
       printf("error at open input in\n");
       return err;
    }

    // get input file stream info
    err = avformat_find_stream_info(inCtx, NULL);
    if (err < 0) {
       printf("error at find stream info\n");
       return err;
    }

    // get info about video
    av_dump_format(inCtx, 0, inputPath, 0);

    // find video input stream
    int vs = -1;
    int s;
    for (s = 0; s < inCtx->nb_streams; ++s) {
       if (inCtx->streams[s] && inCtx->streams[s]->codec && inCtx->streams[s]->codec->codec_type == AVMEDIA_TYPE_VIDEO) {
           vs = s;
           break;
       }
    }

    // check if video stream is valid
    if (vs == -1) {
       printf("error at open video stream\n");
       return -1;
    }

    // set output format
    AVOutputFormat * outFmt = av_guess_format(outFileType, NULL, NULL);
    if (!outFmt) {
       printf("error at output format\n");
       return -1;
    }

    // get an output context to write to
    AVFormatContext *outCtx = NULL;
    err = avformat_alloc_output_context2(&outCtx, outFmt, NULL, NULL);
    if (err < 0 || !outCtx) {
       printf("error at output context\n");
       return err;
    }

    // input and output stream
    AVStream *outStrm = avformat_new_stream(outCtx, NULL);
    AVStream *inStrm = inCtx->streams[vs];

    // add a new codec for the output stream
    AVCodec *codec = NULL;
    avcodec_get_context_defaults3(outStrm->codec, codec);

    outStrm->codec->thread_count = 1;

    outStrm->codec->coder_type = AVMEDIA_TYPE_VIDEO;

    if(outCtx->oformat->flags & AVFMT_GLOBALHEADER) {
       outStrm->codec->flags |= CODEC_FLAG_GLOBAL_HEADER;
    }

    outStrm->codec->sample_aspect_ratio = outStrm->sample_aspect_ratio = inStrm->sample_aspect_ratio;

    err = avio_open(&outCtx->pb, outPath, AVIO_FLAG_WRITE);
    if (err < 0) {
       printf("error at opening outpath\n");
       return err;
    }

    outStrm->disposition = inStrm->disposition;
    outStrm->codec->bits_per_raw_sample = inStrm->codec->bits_per_raw_sample;
    outStrm->codec->chroma_sample_location = inStrm->codec->chroma_sample_location;
    outStrm->codec->codec_id = inStrm->codec->codec_id;
    outStrm->codec->codec_type = inStrm->codec->codec_type;

    if (!outStrm->codec->codec_tag) {
       if (! outCtx->oformat->codec_tag
           || av_codec_get_id (outCtx->oformat->codec_tag, inStrm->codec->codec_tag) == outStrm->codec->codec_id
           || av_codec_get_tag(outCtx->oformat->codec_tag, inStrm->codec->codec_id) <= 0) {
           outStrm->codec->codec_tag = inStrm->codec->codec_tag;
       }
    }

    outStrm->codec->bit_rate = inStrm->codec->bit_rate;
    outStrm->codec->rc_max_rate = inStrm->codec->rc_max_rate;
    outStrm->codec->rc_buffer_size = inStrm->codec->rc_buffer_size;

    const size_t extra_size_alloc = (inStrm->codec->extradata_size > 0) ?
    (inStrm->codec->extradata_size + FF_INPUT_BUFFER_PADDING_SIZE) :
    0;

    if (extra_size_alloc) {
       outStrm->codec->extradata = (uint8_t*)av_mallocz(extra_size_alloc);
       memcpy( outStrm->codec->extradata, inStrm->codec->extradata, inStrm->codec->extradata_size);
    }

    outStrm->codec->extradata_size = inStrm->codec->extradata_size;

    AVRational input_time_base = inStrm->time_base;
    AVRational frameRate = {25, 1};
    if (inStrm->r_frame_rate.num && inStrm->r_frame_rate.den
       && (1.0 * inStrm->r_frame_rate.num / inStrm->r_frame_rate.den < 1000.0)) {
       frameRate.num = inStrm->r_frame_rate.num;
       frameRate.den = inStrm->r_frame_rate.den;
    }

    outStrm->r_frame_rate = frameRate;
    outStrm->codec->time_base = inStrm->codec->time_base;

    outStrm->codec->pix_fmt = inStrm->codec->pix_fmt;
    outStrm->codec->width = width;
    outStrm->codec->height =  height;
    outStrm->codec->has_b_frames =  inStrm->codec->has_b_frames;

    if (!outStrm->codec->sample_aspect_ratio.num) {
       AVRational r0 = {0, 1};
       outStrm->codec->sample_aspect_ratio =
       outStrm->sample_aspect_ratio =
       inStrm->sample_aspect_ratio.num ? inStrm->sample_aspect_ratio :
       inStrm->codec->sample_aspect_ratio.num ?
       inStrm->codec->sample_aspect_ratio : r0;
    }

    avformat_write_header(outCtx, NULL);

    filterGraph = avfilter_graph_alloc();
    if (!filterGraph) {
       printf("could not open filter graph");
       return -1;
    }

    AVFilter *crop = avfilter_get_by_name("crop");
    AVFilter *buffer = avfilter_get_by_name("buffer");
    AVFilter *buffersink = avfilter_get_by_name("buffersink");

    char args[512];

    snprintf(args, sizeof(args), "video_size=%dx%d:pix_fmt=%d:time_base=%d/%d:pixel_aspect=%d/%d",
            width, height, inStrm->codec->pix_fmt,
            inStrm->codec->time_base.num, inStrm->codec->time_base.den,
            inStrm->codec->sample_aspect_ratio.num, inStrm->codec->sample_aspect_ratio.den);

    err = avfilter_graph_create_filter(&buffer_ctx, buffer, NULL, args, NULL, filterGraph);
    if (err < 0) {
       printf("error initializing buffer filter\n");
       return err;
    }

    err = avfilter_graph_create_filter(&buffersink_ctx, buffersink, NULL, NULL, NULL, filterGraph);
    if (err < 0) {
       printf("unable to create buffersink filter\n");
       return err;
    }
    snprintf(args, sizeof(args), "%d:%d", width, height);
    err = avfilter_graph_create_filter(&crop_ctx, crop, NULL, args, NULL, filterGraph);
    if (err < 0) {
       printf("error initializing crop filter\n");
       return err;
    }

    err = avfilter_link(buffer_ctx, 0, crop_ctx, 0);
    if (err < 0) {
       printf("error linking filters\n");
       return err;
    }

    err = avfilter_link(crop_ctx, 0, buffersink_ctx, 0);
    if (err < 0) {
       printf("error linking filters\n");
       return err;
    }

    err = avfilter_graph_config(filterGraph, NULL);
    if (err < 0) {
       printf("error configuring the filter graph\n");
       return err;
    }

    printf("filtergraph configured\n");

    for (;;) {

       AVPacket packet = {0};
       av_init_packet(&packet);

       err = AVERROR(EAGAIN);
       while (AVERROR(EAGAIN) == err)
           err = av_read_frame(inCtx, &packet);

       if (err < 0) {
           if (AVERROR_EOF != err && AVERROR(EIO) != err) {
               printf("eof error\n");
               return 1;
           } else {
               break;
           }
       }

       if (packet.stream_index == vs) {

           //
           //            AVPacket pkt_temp_;
           //            memset(&pkt_temp_, 0, sizeof(pkt_temp_));
           //            AVPacket *pkt_temp = &pkt_temp_;
           //
           //            *pkt_temp = packet;
           //
           //            int error, got_frame;
           //            int new_packet = 1;
           //
           //            error = avcodec_decode_video2(inStrm->codec, frame, &got_frame, pkt_temp);
           //            if(error < 0) {
           //                LOGE("error %d", error);
           //            }
           //
           //            // if (error >= 0) {
           //
           //            // push the video data from decoded frame into the filtergraph
           //            int err = av_buffersrc_write_frame(buffer_ctx, frame);
           //            if (err < 0) {
           //                LOGE("error writing frame to buffersrc");
           //                return -1;
           //            }
           //            // pull filtered video from the filtergraph
           //            for (;;) {
           //                int err = av_buffersink_get_frame(buffersink_ctx, oframe);
           //                if (err == AVERROR_EOF || err == AVERROR(EAGAIN))
           //                    break;
           //                if (err < 0) {
           //                    LOGE("error reading buffer from buffersink");
           //                    return -1;
           //                }
           //            }
           //
           //            LOGI("output frame");

           err = av_interleaved_write_frame(outCtx, &packet);
           if (err < 0) {
               printf("error at write frame");
               return -1;
           }

           //}
       }

       av_free_packet(&packet);
    }

    av_write_trailer(outCtx);
    if (!(outCtx->oformat->flags & AVFMT_NOFILE) && outCtx->pb)
       avio_close(outCtx->pb);

    avformat_free_context(outCtx);
    avformat_close_input(&inCtx);

    return 0;

    }

  • Revision ccef8842d2 : Allow full coeff probability model and cost update This commit moves the simpli

    13 août 2014, par Jingning Han

    Changed Paths :
     Modify /vp9/encoder/vp9_speed_features.c



    Allow full coeff probability model and cost update

    This commit moves the simplified coefficient probability model
    and costing update to speed 4, and turns on chessboard pattern
    mode search for sub 720p sequences. The overall coding performance
    of speed 3 is improved :
    derf 0.889%
    stdhd 1.744%

    The speed 3 runtime for test sequences are improved :
    bus cif at 1000 kbps 9823 ms -> 9642 ms
    pedestrian 1080p 2000 kbps 189559 ms -> 183284 ms

    Change-Id : Iecbc7496a68f31fd49fb09f8dfd97c028d675a5d

  • Revision 1e30547984 : Skip mode search based on reference frame consistency This commit enables the e

    12 août 2014, par Jingning Han

    Changed Paths :
     Modify /vp9/encoder/vp9_rdopt.c



    Skip mode search based on reference frame consistency

    This commit enables the encoder to skip NEARMV and ZEROMV if the
    above and left blocks have identical reference frame, and the
    current reference is different from that. It reduces the runtime
    of speed 3 for test sequences :
    bus cif at 1000 kbps 10064 ms -> 9823 ms
    pedestrian 1080p at 2000 kbps 193078 ms -> 189559 ms

    The compression performance is changed by
    derf -0.085%
    stdhd -0.103%

    Change-Id : If304f26d42e6412152a84c3dd7b02635c38444f4