/* * Copyright (c) 2010 Nicolas George * Copyright (c) 2011 Stefano Sabatini * * 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 * API example for decoding and filtering */ #define _XOPEN_SOURCE 600 /* for usleep */ #include #include #include #include #include #include const char *filter_descr = "scale=78:24"; static AVFormatContext *fmt_ctx; static AVCodecContext *dec_ctx; AVFilterContext *buffersink_ctx; AVFilterContext *buffersrc_ctx; AVFilterGraph *filter_graph; static int video_stream_index = -1; static int64_t last_pts = AV_NOPTS_VALUE; static int open_input_file(const char *filename) { int ret; AVCodec *dec; if ((ret = avformat_open_input(&fmt_ctx, filename, NULL, NULL)) < 0) { av_log(NULL, AV_LOG_ERROR, "Cannot open input file\n"); return ret; } if ((ret = avformat_find_stream_info(fmt_ctx, NULL)) < 0) { av_log(NULL, AV_LOG_ERROR, "Cannot find stream information\n"); return ret; } /* select the video stream */ ret = av_find_best_stream(fmt_ctx, AVMEDIA_TYPE_VIDEO, -1, -1, &dec, 0); if (ret < 0) { av_log(NULL, AV_LOG_ERROR, "Cannot find a video stream in the input file\n"); return ret; } video_stream_index = ret; dec_ctx = fmt_ctx->streams[video_stream_index]->codec; /* init the video decoder */ if ((ret = avcodec_open2(dec_ctx, dec, NULL)) < 0) { av_log(NULL, AV_LOG_ERROR, "Cannot open video decoder\n"); return ret; } return 0; } static int init_filters(const char *filters_descr) { char args[512]; int ret; AVFilter *buffersrc = avfilter_get_by_name("buffer"); AVFilter *buffersink = avfilter_get_by_name("buffersink"); AVFilterInOut *outputs = avfilter_inout_alloc(); AVFilterInOut *inputs = avfilter_inout_alloc(); enum PixelFormat pix_fmts[] = { PIX_FMT_GRAY8, PIX_FMT_NONE }; filter_graph = avfilter_graph_alloc(); /* buffer video source: the decoded frames from the decoder will be inserted here. */ snprintf(args, sizeof(args), "%d:%d:%d:%d:%d:%d:%d", dec_ctx->width, dec_ctx->height, dec_ctx->pix_fmt, dec_ctx->time_base.num, dec_ctx->time_base.den, dec_ctx->sample_aspect_ratio.num, dec_ctx->sample_aspect_ratio.den); ret = avfilter_graph_create_filter(&buffersrc_ctx, buffersrc, "in", args, NULL, filter_graph); if (ret < 0) { av_log(NULL, AV_LOG_ERROR, "Cannot create buffer source\n"); return ret; } /* buffer video sink: to terminate the filter chain. */ ret = avfilter_graph_create_filter(&buffersink_ctx, buffersink, "out", NULL, pix_fmts, filter_graph); if (ret < 0) { av_log(NULL, AV_LOG_ERROR, "Cannot create buffer sink\n"); return ret; } /* Endpoints for the filter graph. */ outputs->name = av_strdup("in"); outputs->filter_ctx = buffersrc_ctx; outputs->pad_idx = 0; outputs->next = NULL; inputs->name = av_strdup("out"); inputs->filter_ctx = buffersink_ctx; inputs->pad_idx = 0; inputs->next = NULL; if ((ret = avfilter_graph_parse(filter_graph, filters_descr, &inputs, &outputs, NULL)) < 0) return ret; if ((ret = avfilter_graph_config(filter_graph, NULL)) < 0) return ret; return 0; } static void display_picref(AVFilterBufferRef *picref, AVRational time_base) { int x, y; uint8_t *p0, *p; int64_t delay; if (picref->pts != AV_NOPTS_VALUE) { if (last_pts != AV_NOPTS_VALUE) { /* sleep roughly the right amount of time; * usleep is in microseconds, just like AV_TIME_BASE. */ delay = av_rescale_q(picref->pts - last_pts, time_base, AV_TIME_BASE_Q); if (delay > 0 && delay < 1000000) usleep(delay); } last_pts = picref->pts; } /* Trivial ASCII grayscale display. */ p0 = picref->data[0]; puts("\033c"); for (y = 0; y < picref->video->h; y++) { p = p0; for (x = 0; x < picref->video->w; x++) putchar(" .-+#"[*(p++) / 52]); putchar('\n'); p0 += picref->linesize[0]; } fflush(stdout); } int main(int argc, char **argv) { int ret; AVPacket packet; AVFrame frame; int got_frame; if (argc != 2) { fprintf(stderr, "Usage: %s file\n", argv[0]); exit(1); } avcodec_register_all(); av_register_all(); avfilter_register_all(); if ((ret = open_input_file(argv[1])) < 0) goto end; if ((ret = init_filters(filter_descr)) < 0) goto end; /* read all packets */ while (1) { AVFilterBufferRef *picref; if ((ret = av_read_frame(fmt_ctx, &packet)) < 0) break; if (packet.stream_index == video_stream_index) { avcodec_get_frame_defaults(&frame); got_frame = 0; ret = avcodec_decode_video2(dec_ctx, &frame, &got_frame, &packet); av_free_packet(&packet); if (ret < 0) { av_log(NULL, AV_LOG_ERROR, "Error decoding video\n"); break; } if (got_frame) { frame.pts = av_frame_get_best_effort_timestamp(&frame); /* push the decoded frame into the filtergraph */ av_vsrc_buffer_add_frame(buffersrc_ctx, &frame, 0); /* pull filtered pictures from the filtergraph */ while (avfilter_poll_frame(buffersink_ctx->inputs[0])) { av_buffersink_get_buffer_ref(buffersink_ctx, &picref, 0); if (picref) { display_picref(picref, buffersink_ctx->inputs[0]->time_base); avfilter_unref_buffer(picref); } } } } } end: avfilter_graph_free(&filter_graph); if (dec_ctx) avcodec_close(dec_ctx); avformat_close_input(&fmt_ctx); if (ret < 0 && ret != AVERROR_EOF) { char buf[1024]; av_strerror(ret, buf, sizeof(buf)); fprintf(stderr, "Error occurred: %s\n", buf); exit(1); } exit(0); }