[deb_ffmpeg.git] / ffmpeg / doc / examples / filtering_video.c

/*
 * 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
 * @example filtering_video.c
 */

#define _XOPEN_SOURCE 600 /* for usleep */
#include <unistd.h>

#include <libavcodec/avcodec.h>
#include <libavformat/avformat.h>
#include <libavfilter/avfiltergraph.h>
#include <libavfilter/avcodec.h>
#include <libavfilter/buffersink.h>
#include <libavfilter/buffersrc.h>
#include <libavutil/opt.h>

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;
    av_opt_set_int(dec_ctx, "refcounted_frames", 1, 0);

    /* 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 = 0;
    AVFilter *buffersrc  = avfilter_get_by_name("buffer");
    AVFilter *buffersink = avfilter_get_by_name("buffersink");
    AVFilterInOut *outputs = avfilter_inout_alloc();
    AVFilterInOut *inputs  = avfilter_inout_alloc();
    AVRational time_base = fmt_ctx->streams[video_stream_index]->time_base;
    enum AVPixelFormat pix_fmts[] = { AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE };

    filter_graph = avfilter_graph_alloc();
    if (!outputs || !inputs || !filter_graph) {
        ret = AVERROR(ENOMEM);
        goto end;
    }

    /* buffer video source: the decoded frames from the decoder will be inserted here. */
    snprintf(args, sizeof(args),
            "video_size=%dx%d:pix_fmt=%d:time_base=%d/%d:pixel_aspect=%d/%d",
            dec_ctx->width, dec_ctx->height, dec_ctx->pix_fmt,
            time_base.num, 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");
        goto end;
    }

    /* buffer video sink: to terminate the filter chain. */
    ret = avfilter_graph_create_filter(&buffersink_ctx, buffersink, "out",
                                       NULL, NULL, filter_graph);
    if (ret < 0) {
        av_log(NULL, AV_LOG_ERROR, "Cannot create buffer sink\n");
        goto end;
    }

    ret = av_opt_set_int_list(buffersink_ctx, "pix_fmts", pix_fmts,
                              AV_PIX_FMT_NONE, AV_OPT_SEARCH_CHILDREN);
    if (ret < 0) {
        av_log(NULL, AV_LOG_ERROR, "Cannot set output pixel format\n");
        goto end;
    }

    /* 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_ptr(filter_graph, filters_descr,
                                    &inputs, &outputs, NULL)) < 0)
        goto end;

    if ((ret = avfilter_graph_config(filter_graph, NULL)) < 0)
        goto end;

end:
    avfilter_inout_free(&inputs);
    avfilter_inout_free(&outputs);

    return ret;
}

static void display_frame(const AVFrame *frame, AVRational time_base)
{
    int x, y;
    uint8_t *p0, *p;
    int64_t delay;

    if (frame->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(frame->pts - last_pts,
                                 time_base, AV_TIME_BASE_Q);
            if (delay > 0 && delay < 1000000)
                usleep(delay);
        }
        last_pts = frame->pts;
    }

    /* Trivial ASCII grayscale display. */
    p0 = frame->data[0];
    puts("\033c");
    for (y = 0; y < frame->height; y++) {
        p = p0;
        for (x = 0; x < frame->width; x++)
            putchar(" .-+#"[*(p++) / 52]);
        putchar('\n');
        p0 += frame->linesize[0];
    }
    fflush(stdout);
}

int main(int argc, char **argv)
{
    int ret;
    AVPacket packet;
    AVFrame *frame = av_frame_alloc();
    AVFrame *filt_frame = av_frame_alloc();
    int got_frame;

    if (!frame || !filt_frame) {
        perror("Could not allocate frame");
        exit(1);
    }
    if (argc != 2) {
        fprintf(stderr, "Usage: %s file\n", argv[0]);
        exit(1);
    }

    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) {
        if ((ret = av_read_frame(fmt_ctx, &packet)) < 0)
            break;

        if (packet.stream_index == video_stream_index) {
            got_frame = 0;
            ret = avcodec_decode_video2(dec_ctx, frame, &got_frame, &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 */
                if (av_buffersrc_add_frame_flags(buffersrc_ctx, frame, AV_BUFFERSRC_FLAG_KEEP_REF) < 0) {
                    av_log(NULL, AV_LOG_ERROR, "Error while feeding the filtergraph\n");
                    break;
                }

                /* pull filtered frames from the filtergraph */
                while (1) {
                    ret = av_buffersink_get_frame(buffersink_ctx, filt_frame);
                    if (ret == AVERROR(EAGAIN) || ret == AVERROR_EOF)
                        break;
                    if (ret < 0)
                        goto end;
                    display_frame(filt_frame, buffersink_ctx->inputs[0]->time_base);
                    av_frame_unref(filt_frame);
                }
                av_frame_unref(frame);
            }
        }
        av_free_packet(&packet);
    }
end:
    avfilter_graph_free(&filter_graph);
    avcodec_close(dec_ctx);
    avformat_close_input(&fmt_ctx);
    av_frame_free(&frame);
    av_frame_free(&filt_frame);

    if (ret < 0 && ret != AVERROR_EOF) {
        fprintf(stderr, "Error occurred: %s\n", av_err2str(ret));
        exit(1);
    }

    exit(0);
}
Commit	Line	Data
2ba45a60 DM	1	/*
	2	* Copyright (c) 2010 Nicolas George
	3	* Copyright (c) 2011 Stefano Sabatini
	4	*
	5	* Permission is hereby granted, free of charge, to any person obtaining a copy
	6	* of this software and associated documentation files (the "Software"), to deal
	7	* in the Software without restriction, including without limitation the rights
	8	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	9	* copies of the Software, and to permit persons to whom the Software is
	10	* furnished to do so, subject to the following conditions:
	11	*
	12	* The above copyright notice and this permission notice shall be included in
	13	* all copies or substantial portions of the Software.
	14	*
	15	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	16	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	17	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
	18	* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	19	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	20	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
	21	* THE SOFTWARE.
	22	*/
	23
	24	/**
	25	* @file
	26	* API example for decoding and filtering
	27	* @example filtering_video.c
	28	*/
	29
	30	#define _XOPEN_SOURCE 600 /* for usleep */
	31	#include <unistd.h>
	32
	33	#include <libavcodec/avcodec.h>
	34	#include <libavformat/avformat.h>
	35	#include <libavfilter/avfiltergraph.h>
	36	#include <libavfilter/avcodec.h>
	37	#include <libavfilter/buffersink.h>
	38	#include <libavfilter/buffersrc.h>
	39	#include <libavutil/opt.h>
	40
	41	const char *filter_descr = "scale=78:24";
	42
	43	static AVFormatContext *fmt_ctx;
	44	static AVCodecContext *dec_ctx;
	45	AVFilterContext *buffersink_ctx;
	46	AVFilterContext *buffersrc_ctx;
	47	AVFilterGraph *filter_graph;
	48	static int video_stream_index = -1;
	49	static int64_t last_pts = AV_NOPTS_VALUE;
	50
	51	static int open_input_file(const char *filename)
	52	{
	53	int ret;
	54	AVCodec *dec;
	55
	56	if ((ret = avformat_open_input(&fmt_ctx, filename, NULL, NULL)) < 0) {
	57	av_log(NULL, AV_LOG_ERROR, "Cannot open input file\n");
	58	return ret;
	59	}
	60
	61	if ((ret = avformat_find_stream_info(fmt_ctx, NULL)) < 0) {
	62	av_log(NULL, AV_LOG_ERROR, "Cannot find stream information\n");
	63	return ret;
	64	}
65
66	/* select the video stream */
67	ret = av_find_best_stream(fmt_ctx, AVMEDIA_TYPE_VIDEO, -1, -1, &dec, 0);
68	if (ret < 0) {
69	av_log(NULL, AV_LOG_ERROR, "Cannot find a video stream in the input file\n");
70	return ret;
71	}
72	video_stream_index = ret;
73	dec_ctx = fmt_ctx->streams[video_stream_index]->codec;
74	av_opt_set_int(dec_ctx, "refcounted_frames", 1, 0);
75
76	/* init the video decoder */
77	if ((ret = avcodec_open2(dec_ctx, dec, NULL)) < 0) {
78	av_log(NULL, AV_LOG_ERROR, "Cannot open video decoder\n");
79	return ret;
80	}
81
82	return 0;
83	}
84
85	static int init_filters(const char *filters_descr)
86	{
87	char args[512];
88	int ret = 0;
89	AVFilter *buffersrc = avfilter_get_by_name("buffer");
90	AVFilter *buffersink = avfilter_get_by_name("buffersink");
91	AVFilterInOut *outputs = avfilter_inout_alloc();
92	AVFilterInOut *inputs = avfilter_inout_alloc();
dcebb6f3	93	AVRational time_base = fmt_ctx->streams[video_stream_index]->time_base;
2ba45a60 DM	94	enum AVPixelFormat pix_fmts[] = { AV_PIX_FMT_GRAY8, AV_PIX_FMT_NONE };
	95
	96	filter_graph = avfilter_graph_alloc();
	97	if (!outputs \|\| !inputs \|\| !filter_graph) {
	98	ret = AVERROR(ENOMEM);
	99	goto end;
	100	}
	101
	102	/* buffer video source: the decoded frames from the decoder will be inserted here. */
	103	snprintf(args, sizeof(args),
	104	"video_size=%dx%d:pix_fmt=%d:time_base=%d/%d:pixel_aspect=%d/%d",
	105	dec_ctx->width, dec_ctx->height, dec_ctx->pix_fmt,
dcebb6f3	106	time_base.num, time_base.den,
2ba45a60 DM	107	dec_ctx->sample_aspect_ratio.num, dec_ctx->sample_aspect_ratio.den);
	108
	109	ret = avfilter_graph_create_filter(&buffersrc_ctx, buffersrc, "in",
	110	args, NULL, filter_graph);
	111	if (ret < 0) {
	112	av_log(NULL, AV_LOG_ERROR, "Cannot create buffer source\n");
	113	goto end;
	114	}
	115
	116	/* buffer video sink: to terminate the filter chain. */
	117	ret = avfilter_graph_create_filter(&buffersink_ctx, buffersink, "out",
	118	NULL, NULL, filter_graph);
	119	if (ret < 0) {
	120	av_log(NULL, AV_LOG_ERROR, "Cannot create buffer sink\n");
	121	goto end;
	122	}
	123
	124	ret = av_opt_set_int_list(buffersink_ctx, "pix_fmts", pix_fmts,
	125	AV_PIX_FMT_NONE, AV_OPT_SEARCH_CHILDREN);
	126	if (ret < 0) {
	127	av_log(NULL, AV_LOG_ERROR, "Cannot set output pixel format\n");
	128	goto end;
	129	}
	130
	131	/* Endpoints for the filter graph. */
	132	outputs->name = av_strdup("in");
	133	outputs->filter_ctx = buffersrc_ctx;
	134	outputs->pad_idx = 0;
	135	outputs->next = NULL;
	136
	137	inputs->name = av_strdup("out");
	138	inputs->filter_ctx = buffersink_ctx;
	139	inputs->pad_idx = 0;
	140	inputs->next = NULL;
	141
	142	if ((ret = avfilter_graph_parse_ptr(filter_graph, filters_descr,
	143	&inputs, &outputs, NULL)) < 0)
	144	goto end;
	145
	146	if ((ret = avfilter_graph_config(filter_graph, NULL)) < 0)
	147	goto end;
	148
	149	end:
	150	avfilter_inout_free(&inputs);
	151	avfilter_inout_free(&outputs);
	152
	153	return ret;
	154	}
	155
	156	static void display_frame(const AVFrame *frame, AVRational time_base)
	157	{
	158	int x, y;
	159	uint8_t p0, p;
	160	int64_t delay;
	161
	162	if (frame->pts != AV_NOPTS_VALUE) {
	163	if (last_pts != AV_NOPTS_VALUE) {
	164	/* sleep roughly the right amount of time;
	165	* usleep is in microseconds, just like AV_TIME_BASE. */
	166	delay = av_rescale_q(frame->pts - last_pts,
	167	time_base, AV_TIME_BASE_Q);
	168	if (delay > 0 && delay < 1000000)
	169	usleep(delay);
	170	}
171	last_pts = frame->pts;
172	}
173
174	/* Trivial ASCII grayscale display. */
175	p0 = frame->data[0];
176	puts("\033c");
177	for (y = 0; y < frame->height; y++) {
178	p = p0;
179	for (x = 0; x < frame->width; x++)
180	putchar(" .-+#"[*(p++) / 52]);
181	putchar('\n');
182	p0 += frame->linesize[0];
183	}
184	fflush(stdout);
185	}
186
187	int main(int argc, char **argv)
188	{
189	int ret;
190	AVPacket packet;
191	AVFrame *frame = av_frame_alloc();
192	AVFrame *filt_frame = av_frame_alloc();
193	int got_frame;
194
195	if (!frame \|\| !filt_frame) {
196	perror("Could not allocate frame");
197	exit(1);
198	}
199	if (argc != 2) {
200	fprintf(stderr, "Usage: %s file\n", argv[0]);
201	exit(1);
202	}
203
204	av_register_all();
205	avfilter_register_all();
206
207	if ((ret = open_input_file(argv[1])) < 0)
208	goto end;
209	if ((ret = init_filters(filter_descr)) < 0)
210	goto end;
211
212	/* read all packets */
213	while (1) {
214	if ((ret = av_read_frame(fmt_ctx, &packet)) < 0)
215	break;
216
217	if (packet.stream_index == video_stream_index) {
218	got_frame = 0;
219	ret = avcodec_decode_video2(dec_ctx, frame, &got_frame, &packet);
220	if (ret < 0) {
221	av_log(NULL, AV_LOG_ERROR, "Error decoding video\n");
222	break;
223	}
224
225	if (got_frame) {
226	frame->pts = av_frame_get_best_effort_timestamp(frame);
227
228	/* push the decoded frame into the filtergraph */
229	if (av_buffersrc_add_frame_flags(buffersrc_ctx, frame, AV_BUFFERSRC_FLAG_KEEP_REF) < 0) {
230	av_log(NULL, AV_LOG_ERROR, "Error while feeding the filtergraph\n");
231	break;
232	}
233
234	/* pull filtered frames from the filtergraph */
235	while (1) {
236	ret = av_buffersink_get_frame(buffersink_ctx, filt_frame);
237	if (ret == AVERROR(EAGAIN) \|\| ret == AVERROR_EOF)
238	break;
239	if (ret < 0)
240	goto end;
241	display_frame(filt_frame, buffersink_ctx->inputs[0]->time_base);
242	av_frame_unref(filt_frame);
243	}
244	av_frame_unref(frame);
245	}
246	}
247	av_free_packet(&packet);
248	}
249	end:
250	avfilter_graph_free(&filter_graph);
251	avcodec_close(dec_ctx);
252	avformat_close_input(&fmt_ctx);
253	av_frame_free(&frame);
254	av_frame_free(&filt_frame);
255
256	if (ret < 0 && ret != AVERROR_EOF) {
257	fprintf(stderr, "Error occurred: %s\n", av_err2str(ret));
258	exit(1);
259	}
260
261	exit(0);
262	}