/* * Copyright (c) 2017 Jun Zhao * Copyright (c) 2017 Kaixuan Liu * * HW Acceleration API (video decoding) decode sample * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN * THE SOFTWARE. */ /** * @file HW-accelerated decoding API usage.example * @example hw_decode.c * * Perform HW-accelerated decoding with output frames from HW video * surfaces. */ #include <stdio.h> #include <libavcodec/avcodec.h>#include <libavformat/avformat.h>#include <libavutil/mem.h>#include <libavutil/pixdesc.h>#include <libavutil/hwcontext.h>#include <libavutil/opt.h>#include <libavutil/avassert.h>#include <libavutil/imgutils.h> static AVBufferRef *hw_device_ctx = NULL;static enum AVPixelFormat hw_pix_fmt;static FILE *output_file = NULL; static int hw_decoder_init(AVCodecContext *ctx, const enum AVHWDeviceType type){    int err = 0;     if ((err = av_hwdevice_ctx_create(&hw_device_ctx, type,                                      NULL, NULL, 0)) < 0) {        fprintf(stderr, "Failed to create specified HW device.\n");        return err;    }    ctx->hw_device_ctx = av_buffer_ref(hw_device_ctx);     return err;} static enum AVPixelFormat get_hw_format(AVCodecContext *ctx,                                        const enum AVPixelFormat *pix_fmts){    const enum AVPixelFormat *p;     for (p = pix_fmts; *p != -1; p++) {        if (*p == hw_pix_fmt)            return *p;    }     fprintf(stderr, "Failed to get HW surface format.\n");    return AV_PIX_FMT_NONE;} static int decode_write(AVCodecContext *avctx, AVPacket *packet){    AVFrame *frame = NULL, *sw_frame = NULL;    AVFrame *tmp_frame = NULL;    uint8_t *buffer = NULL;    int size;    int ret = 0;     ret = avcodec_send_packet(avctx, packet);    if (ret < 0) {        fprintf(stderr, "Error during decoding\n");        return ret;    }     while (1) {        if (!(frame = av_frame_alloc()) || !(sw_frame = av_frame_alloc())) {            fprintf(stderr, "Can not alloc frame\n");            ret = AVERROR(ENOMEM);            goto fail;        }         ret = avcodec_receive_frame(avctx, frame);        if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF) {            av_frame_free(&frame);            av_frame_free(&sw_frame);            return 0;        } else if (ret < 0) {            fprintf(stderr, "Error while decoding\n");            goto fail;        }         if (frame->format == hw_pix_fmt) {            /* retrieve data from GPU to CPU */            if ((ret = av_hwframe_transfer_data(sw_frame, frame, 0)) < 0) {                fprintf(stderr, "Error transferring the data to system memory\n");                goto fail;            }            tmp_frame = sw_frame;        } else            tmp_frame = frame;         size = av_image_get_buffer_size(tmp_frame->format, tmp_frame->width,                                        tmp_frame->height, 1);        buffer = av_malloc(size);        if (!buffer) {            fprintf(stderr, "Can not alloc buffer\n");            ret = AVERROR(ENOMEM);            goto fail;        }        ret = av_image_copy_to_buffer(buffer, size,                                      (const uint8_t * const *)tmp_frame->data,                                      (const int *)tmp_frame->linesize, tmp_frame->format,                                      tmp_frame->width, tmp_frame->height, 1);        if (ret < 0) {            fprintf(stderr, "Can not copy image to buffer\n");            goto fail;        }         if ((ret = fwrite(buffer, 1, size, output_file)) < 0) {            fprintf(stderr, "Failed to dump raw data.\n");            goto fail;        }     fail:        av_frame_free(&frame);        av_frame_free(&sw_frame);        av_freep(&buffer);        if (ret < 0)            return ret;    }} int main(int argc, char *argv[]){    AVFormatContext *input_ctx = NULL;    int video_stream, ret;    AVStream *video = NULL;    AVCodecContext *decoder_ctx = NULL;    const AVCodec *decoder = NULL;    AVPacket *packet = NULL;    enum AVHWDeviceType type;    int i;     if (argc < 4) {        fprintf(stderr, "Usage: %s <device type> <input file> <output file>\n", argv[0]);        return -1;    }     type = av_hwdevice_find_type_by_name(argv[1]);    if (type == AV_HWDEVICE_TYPE_NONE) {        fprintf(stderr, "Device type %s is not supported.\n", argv[1]);        fprintf(stderr, "Available device types:");        while((type = av_hwdevice_iterate_types(type)) != AV_HWDEVICE_TYPE_NONE)            fprintf(stderr, " %s", av_hwdevice_get_type_name(type));        fprintf(stderr, "\n");        return -1;    }     packet = av_packet_alloc();    if (!packet) {        fprintf(stderr, "Failed to allocate AVPacket\n");        return -1;    }     /* open the input file */    if (avformat_open_input(&input_ctx, argv[2], NULL, NULL) != 0) {        fprintf(stderr, "Cannot open input file '%s'\n", argv[2]);        return -1;    }     if (avformat_find_stream_info(input_ctx, NULL) < 0) {        fprintf(stderr, "Cannot find input stream information.\n");        return -1;    }     /* find the video stream information */    ret = av_find_best_stream(input_ctx, AVMEDIA_TYPE_VIDEO, -1, -1, &decoder, 0);    if (ret < 0) {        fprintf(stderr, "Cannot find a video stream in the input file\n");        return -1;    }    video_stream = ret;     for (i = 0;; i++) {        const AVCodecHWConfig *config = avcodec_get_hw_config(decoder, i);        if (!config) {            fprintf(stderr, "Decoder %s does not support device type %s.\n",                    decoder->name, av_hwdevice_get_type_name(type));            return -1;        }        if (config->methods & AV_CODEC_HW_CONFIG_METHOD_HW_DEVICE_CTX &&            config->device_type == type) {            hw_pix_fmt = config->pix_fmt;            break;        }    }     if (!(decoder_ctx = avcodec_alloc_context3(decoder)))        return AVERROR(ENOMEM);     video = input_ctx->streams[video_stream];    if (avcodec_parameters_to_context(decoder_ctx, video->codecpar) < 0)        return -1;     decoder_ctx->get_format  = get_hw_format;     if (hw_decoder_init(decoder_ctx, type) < 0)        return -1;     if ((ret = avcodec_open2(decoder_ctx, decoder, NULL)) < 0) {        fprintf(stderr, "Failed to open codec for stream #%u\n", video_stream);        return -1;    }     /* open the file to dump raw data */    output_file = fopen(argv[3], "w+b");     /* actual decoding and dump the raw data */    while (ret >= 0) {        if ((ret = av_read_frame(input_ctx, packet)) < 0)            break;         if (video_stream == packet->stream_index)            ret = decode_write(decoder_ctx, packet);         av_packet_unref(packet);    }     /* flush the decoder */    ret = decode_write(decoder_ctx, NULL);     if (output_file)        fclose(output_file);    av_packet_free(&packet);    avcodec_free_context(&decoder_ctx);    avformat_close_input(&input_ctx);    av_buffer_unref(&hw_device_ctx);     return 0;}