/* * Copyright (c) 2017 Jun Zhao * Copyright (c) 2017 Kaixuan Liu * * HW Acceleration API (video decoding) decode sample * * This file is part of FFmpeg. * * FFmpeg is free software; you can redistribute it and/or * modify it under the terms of the GNU Lesser General Public * License as published by the Free Software Foundation; either * version 2.1 of the License, or (at your option) any later version. * * FFmpeg is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * Lesser General Public License for more details. * * You should have received a copy of the GNU Lesser General Public * License along with FFmpeg; if not, write to the Free Software * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ /** * @file * HW-Accelerated decoding example. * * @example hw_decode.c * This example shows how to do HW-accelerated decoding with output * frames from the HW video surfaces. */ #include #include #include #include #include #include #include #include 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; AVCodec *decoder = NULL; AVPacket packet; enum AVHWDeviceType type; int i; if (argc < 4) { fprintf(stderr, "Usage: %s \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; } /* 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; av_opt_set_int(decoder_ctx, "refcounted_frames", 1, 0); 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+"); /* 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 */ packet.data = NULL; packet.size = 0; ret = decode_write(decoder_ctx, &packet); av_packet_unref(&packet); if (output_file) fclose(output_file); avcodec_free_context(&decoder_ctx); avformat_close_input(&input_ctx); av_buffer_unref(&hw_device_ctx); return 0; }