--- /dev/null
+/*
+ * Various utilities for ffmpeg system
+ * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
+ *
+ * This library 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 of the License, or (at your option) any later version.
+ *
+ * This library 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 this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ */
+#include "avformat.h"
+
+AVInputFormat *first_iformat;
+AVOutputFormat *first_oformat;
+AVImageFormat *first_image_format;
+
+void av_register_input_format(AVInputFormat *format)
+{
+ AVInputFormat **p;
+ p = &first_iformat;
+ while (*p != NULL) p = &(*p)->next;
+ *p = format;
+ format->next = NULL;
+}
+
+void av_register_output_format(AVOutputFormat *format)
+{
+ AVOutputFormat **p;
+ p = &first_oformat;
+ while (*p != NULL) p = &(*p)->next;
+ *p = format;
+ format->next = NULL;
+}
+
+int match_ext(const char *filename, const char *extensions)
+{
+ const char *ext, *p;
+ char ext1[32], *q;
+
+ ext = strrchr(filename, '.');
+ if (ext) {
+ ext++;
+ p = extensions;
+ for(;;) {
+ q = ext1;
+ while (*p != '\0' && *p != ',')
+ *q++ = *p++;
+ *q = '\0';
+ if (!strcasecmp(ext1, ext))
+ return 1;
+ if (*p == '\0')
+ break;
+ p++;
+ }
+ }
+ return 0;
+}
+
+AVOutputFormat *guess_format(const char *short_name, const char *filename,
+ const char *mime_type)
+{
+ AVOutputFormat *fmt, *fmt_found;
+ int score_max, score;
+
+ /* specific test for image sequences */
+ if (!short_name && filename &&
+ filename_number_test(filename) >= 0 &&
+ guess_image_format(filename)) {
+ return guess_format("image", NULL, NULL);
+ }
+
+ /* find the proper file type */
+ fmt_found = NULL;
+ score_max = 0;
+ fmt = first_oformat;
+ while (fmt != NULL) {
+ score = 0;
+ if (fmt->name && short_name && !strcmp(fmt->name, short_name))
+ score += 100;
+ if (fmt->mime_type && mime_type && !strcmp(fmt->mime_type, mime_type))
+ score += 10;
+ if (filename && fmt->extensions &&
+ match_ext(filename, fmt->extensions)) {
+ score += 5;
+ }
+ if (score > score_max) {
+ score_max = score;
+ fmt_found = fmt;
+ }
+ fmt = fmt->next;
+ }
+ return fmt_found;
+}
+
+AVOutputFormat *guess_stream_format(const char *short_name, const char *filename,
+ const char *mime_type)
+{
+ AVOutputFormat *fmt = guess_format(short_name, filename, mime_type);
+
+ if (fmt) {
+ AVOutputFormat *stream_fmt;
+ char stream_format_name[64];
+
+ snprintf(stream_format_name, sizeof(stream_format_name), "%s_stream", fmt->name);
+ stream_fmt = guess_format(stream_format_name, NULL, NULL);
+
+ if (stream_fmt)
+ fmt = stream_fmt;
+ }
+
+ return fmt;
+}
+
+AVInputFormat *av_find_input_format(const char *short_name)
+{
+ AVInputFormat *fmt;
+ for(fmt = first_iformat; fmt != NULL; fmt = fmt->next) {
+ if (!strcmp(fmt->name, short_name))
+ return fmt;
+ }
+ return NULL;
+}
+
+/* memory handling */
+
+/**
+ * Default packet destructor
+ */
+static void av_destruct_packet(AVPacket *pkt)
+{
+ av_free(pkt->data);
+ pkt->data = NULL; pkt->size = 0;
+}
+
+/**
+ * Allocate the payload of a packet and intialized its fields to default values.
+ *
+ * @param pkt packet
+ * @param size wanted payload size
+ * @return 0 if OK. AVERROR_xxx otherwise.
+ */
+int av_new_packet(AVPacket *pkt, int size)
+{
+ void *data = av_malloc(size + FF_INPUT_BUFFER_PADDING_SIZE);
+ if (!data)
+ return AVERROR_NOMEM;
+ memset(data + size, 0, FF_INPUT_BUFFER_PADDING_SIZE);
+
+ av_init_packet(pkt);
+ pkt->data = data;
+ pkt->size = size;
+ pkt->destruct = av_destruct_packet;
+ return 0;
+}
+
+/* fifo handling */
+
+int fifo_init(FifoBuffer *f, int size)
+{
+ f->buffer = av_malloc(size);
+ if (!f->buffer)
+ return -1;
+ f->end = f->buffer + size;
+ f->wptr = f->rptr = f->buffer;
+ return 0;
+}
+
+void fifo_free(FifoBuffer *f)
+{
+ av_free(f->buffer);
+}
+
+int fifo_size(FifoBuffer *f, uint8_t *rptr)
+{
+ int size;
+
+ if (f->wptr >= rptr) {
+ size = f->wptr - rptr;
+ } else {
+ size = (f->end - rptr) + (f->wptr - f->buffer);
+ }
+ return size;
+}
+
+/* get data from the fifo (return -1 if not enough data) */
+int fifo_read(FifoBuffer *f, uint8_t *buf, int buf_size, uint8_t **rptr_ptr)
+{
+ uint8_t *rptr = *rptr_ptr;
+ int size, len;
+
+ if (f->wptr >= rptr) {
+ size = f->wptr - rptr;
+ } else {
+ size = (f->end - rptr) + (f->wptr - f->buffer);
+ }
+
+ if (size < buf_size)
+ return -1;
+ while (buf_size > 0) {
+ len = f->end - rptr;
+ if (len > buf_size)
+ len = buf_size;
+ memcpy(buf, rptr, len);
+ buf += len;
+ rptr += len;
+ if (rptr >= f->end)
+ rptr = f->buffer;
+ buf_size -= len;
+ }
+ *rptr_ptr = rptr;
+ return 0;
+}
+
+void fifo_write(FifoBuffer *f, uint8_t *buf, int size, uint8_t **wptr_ptr)
+{
+ int len;
+ uint8_t *wptr;
+ wptr = *wptr_ptr;
+ while (size > 0) {
+ len = f->end - wptr;
+ if (len > size)
+ len = size;
+ memcpy(wptr, buf, len);
+ wptr += len;
+ if (wptr >= f->end)
+ wptr = f->buffer;
+ buf += len;
+ size -= len;
+ }
+ *wptr_ptr = wptr;
+}
+
+int filename_number_test(const char *filename)
+{
+ char buf[1024];
+ return get_frame_filename(buf, sizeof(buf), filename, 1);
+}
+
+/* guess file format */
+AVInputFormat *av_probe_input_format(AVProbeData *pd, int is_opened)
+{
+ AVInputFormat *fmt1, *fmt;
+ int score, score_max;
+
+ fmt = NULL;
+ score_max = 0;
+ for(fmt1 = first_iformat; fmt1 != NULL; fmt1 = fmt1->next) {
+ if (!is_opened && !(fmt1->flags & AVFMT_NOFILE))
+ continue;
+ score = 0;
+ if (fmt1->read_probe) {
+ score = fmt1->read_probe(pd);
+ } else if (fmt1->extensions) {
+ if (match_ext(pd->filename, fmt1->extensions)) {
+ score = 50;
+ }
+ }
+ if (score > score_max) {
+ score_max = score;
+ fmt = fmt1;
+ }
+ }
+ return fmt;
+}
+
+/************************************************************/
+/* input media file */
+
+#define PROBE_BUF_SIZE 2048
+
+/**
+ * Open a media file as input. The codec are not opened. Only the file
+ * header (if present) is read.
+ *
+ * @param ic_ptr the opened media file handle is put here
+ * @param filename filename to open.
+ * @param fmt if non NULL, force the file format to use
+ * @param buf_size optional buffer size (zero if default is OK)
+ * @param ap additionnal parameters needed when opening the file (NULL if default)
+ * @return 0 if OK. AVERROR_xxx otherwise.
+ */
+int av_open_input_file(AVFormatContext **ic_ptr, const char *filename,
+ AVInputFormat *fmt,
+ int buf_size,
+ AVFormatParameters *ap)
+{
+ AVFormatContext *ic = NULL;
+ int err, must_open_file;
+ char buf[PROBE_BUF_SIZE];
+ AVProbeData probe_data, *pd = &probe_data;
+
+ ic = av_mallocz(sizeof(AVFormatContext));
+ if (!ic) {
+ err = AVERROR_NOMEM;
+ goto fail;
+ }
+ ic->duration = AV_NOPTS_VALUE;
+ ic->start_time = AV_NOPTS_VALUE;
+ pstrcpy(ic->filename, sizeof(ic->filename), filename);
+ pd->filename = ic->filename;
+ pd->buf = buf;
+ pd->buf_size = 0;
+
+ if (!fmt) {
+ /* guess format if no file can be opened */
+ fmt = av_probe_input_format(pd, 0);
+ }
+
+ /* do not open file if the format does not need it. XXX: specific
+ hack needed to handle RTSP/TCP */
+ must_open_file = 1;
+ if ((fmt && (fmt->flags & AVFMT_NOFILE))
+#ifdef CONFIG_NETWORK
+ || (fmt == &rtp_demux && !strcmp(filename, "null"))
+#endif
+ ) {
+ must_open_file = 0;
+ }
+
+ if (!fmt || must_open_file) {
+ /* if no file needed do not try to open one */
+ if (url_fopen(&ic->pb, filename, URL_RDONLY) < 0) {
+ err = AVERROR_IO;
+ goto fail;
+ }
+ if (buf_size > 0) {
+ url_setbufsize(&ic->pb, buf_size);
+ }
+ if (!fmt) {
+ /* read probe data */
+ pd->buf_size = get_buffer(&ic->pb, buf, PROBE_BUF_SIZE);
+ url_fseek(&ic->pb, 0, SEEK_SET);
+ }
+ }
+
+ /* guess file format */
+ if (!fmt) {
+ fmt = av_probe_input_format(pd, 1);
+ }
+
+ /* if still no format found, error */
+ if (!fmt) {
+ err = AVERROR_NOFMT;
+ goto fail1;
+ }
+
+ /* XXX: suppress this hack for redirectors */
+#ifdef CONFIG_NETWORK
+ if (fmt == &redir_demux) {
+ err = redir_open(ic_ptr, &ic->pb);
+ url_fclose(&ic->pb);
+ av_free(ic);
+ return err;
+ }
+#endif
+
+ ic->iformat = fmt;
+
+ /* check filename in case of an image number is expected */
+ if (ic->iformat->flags & AVFMT_NEEDNUMBER) {
+ if (filename_number_test(ic->filename) < 0) {
+ err = AVERROR_NUMEXPECTED;
+ goto fail1;
+ }
+ }
+
+ /* allocate private data */
+ if (fmt->priv_data_size > 0) {
+ ic->priv_data = av_mallocz(fmt->priv_data_size);
+ if (!ic->priv_data) {
+ err = AVERROR_NOMEM;
+ goto fail1;
+ }
+ } else
+ ic->priv_data = NULL;
+
+ /* default pts settings is MPEG like */
+ av_set_pts_info(ic, 33, 1, 90000);
+
+ err = ic->iformat->read_header(ic, ap);
+ if (err < 0)
+ goto fail1;
+ *ic_ptr = ic;
+ return 0;
+ fail1:
+ if (!fmt || must_open_file) {
+ url_fclose(&ic->pb);
+ }
+ fail:
+ if (ic) {
+ av_freep(&ic->priv_data);
+ }
+ av_free(ic);
+ *ic_ptr = NULL;
+ return err;
+}
+
+/**
+ * Read a packet from a media file
+ * @param s media file handle
+ * @param pkt is filled
+ * @return 0 if OK. AVERROR_xxx if error.
+ */
+int av_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+ AVPacketList *pktl;
+
+ pktl = s->packet_buffer;
+ if (pktl) {
+ /* read packet from packet buffer, if there is data */
+ *pkt = pktl->pkt;
+ s->packet_buffer = pktl->next;
+ av_free(pktl);
+ return 0;
+ } else {
+ return s->iformat->read_packet(s, pkt);
+ }
+}
+
+
+/* return TRUE if the stream has accurate timings for at least one component */
+static int av_has_timings(AVFormatContext *ic)
+{
+ int i;
+ AVStream *st;
+
+ for(i = 0;i < ic->nb_streams; i++) {
+ st = ic->streams[i];
+ if (st->start_time != AV_NOPTS_VALUE &&
+ st->duration != AV_NOPTS_VALUE)
+ return 1;
+ }
+ return 0;
+}
+
+/* estimate the stream timings from the one of each components. Also
+ compute the global bitrate if possible */
+static void av_update_stream_timings(AVFormatContext *ic)
+{
+ int64_t start_time, end_time, end_time1;
+ int i;
+ AVStream *st;
+
+ start_time = MAXINT64;
+ end_time = MININT64;
+ for(i = 0;i < ic->nb_streams; i++) {
+ st = ic->streams[i];
+ if (st->start_time != AV_NOPTS_VALUE) {
+ if (st->start_time < start_time)
+ start_time = st->start_time;
+ if (st->duration != AV_NOPTS_VALUE) {
+ end_time1 = st->start_time + st->duration;
+ if (end_time1 > end_time)
+ end_time = end_time1;
+ }
+ }
+ }
+ if (start_time != MAXINT64) {
+ ic->start_time = start_time;
+ if (end_time != MAXINT64) {
+ ic->duration = end_time - start_time;
+ if (ic->file_size > 0) {
+ /* compute the bit rate */
+ ic->bit_rate = (double)ic->file_size * 8.0 * AV_TIME_BASE /
+ (double)ic->duration;
+ }
+ }
+ }
+
+}
+
+static void fill_all_stream_timings(AVFormatContext *ic)
+{
+ int i;
+ AVStream *st;
+
+ av_update_stream_timings(ic);
+ for(i = 0;i < ic->nb_streams; i++) {
+ st = ic->streams[i];
+ if (st->start_time == AV_NOPTS_VALUE) {
+ st->start_time = ic->start_time;
+ st->duration = ic->duration;
+ }
+ }
+}
+
+static void av_estimate_timings_from_bit_rate(AVFormatContext *ic)
+{
+ int64_t filesize, duration;
+ int bit_rate, i;
+ AVStream *st;
+
+ /* if bit_rate is already set, we believe it */
+ if (ic->bit_rate == 0) {
+ bit_rate = 0;
+ for(i=0;i<ic->nb_streams;i++) {
+ st = ic->streams[i];
+ bit_rate += st->codec.bit_rate;
+ }
+ ic->bit_rate = bit_rate;
+ }
+
+ /* if duration is already set, we believe it */
+ if (ic->duration == AV_NOPTS_VALUE &&
+ ic->bit_rate != 0 &&
+ ic->file_size != 0) {
+ filesize = ic->file_size;
+ if (filesize > 0) {
+ duration = (int64_t)((8 * AV_TIME_BASE * (double)filesize) / (double)ic->bit_rate);
+ for(i = 0; i < ic->nb_streams; i++) {
+ st = ic->streams[i];
+ if (st->start_time == AV_NOPTS_VALUE ||
+ st->duration == AV_NOPTS_VALUE) {
+ st->start_time = 0;
+ st->duration = duration;
+ }
+ }
+ }
+ }
+}
+
+static void flush_packet_queue(AVFormatContext *s)
+{
+ AVPacketList *pktl;
+
+ for(;;) {
+ pktl = s->packet_buffer;
+ if (!pktl)
+ break;
+ s->packet_buffer = pktl->next;
+ av_free_packet(&pktl->pkt);
+ av_free(pktl);
+ }
+}
+
+#define DURATION_MAX_READ_SIZE 250000
+
+/* only usable for MPEG-PS streams */
+static void av_estimate_timings_from_pts(AVFormatContext *ic)
+{
+ AVPacket pkt1, *pkt = &pkt1;
+ AVStream *st;
+ int read_size, i, ret;
+ int64_t start_time, end_time, end_time1;
+ int64_t filesize, offset, duration;
+
+ /* we read the first packets to get the first PTS (not fully
+ accurate, but it is enough now) */
+ url_fseek(&ic->pb, 0, SEEK_SET);
+ read_size = 0;
+ for(;;) {
+ if (read_size >= DURATION_MAX_READ_SIZE)
+ break;
+ /* if all info is available, we can stop */
+ for(i = 0;i < ic->nb_streams; i++) {
+ st = ic->streams[i];
+ if (st->start_time == AV_NOPTS_VALUE)
+ break;
+ }
+ if (i == ic->nb_streams)
+ break;
+
+ ret = av_read_packet(ic, pkt);
+ if (ret != 0)
+ break;
+ read_size += pkt->size;
+ st = ic->streams[pkt->stream_index];
+ if (pkt->pts != AV_NOPTS_VALUE) {
+ if (st->start_time == AV_NOPTS_VALUE)
+ st->start_time = (int64_t)((double)pkt->pts * ic->pts_num * (double)AV_TIME_BASE / ic->pts_den);
+ }
+ av_free_packet(pkt);
+ }
+
+ /* we compute the minimum start_time and use it as default */
+ start_time = MAXINT64;
+ for(i = 0; i < ic->nb_streams; i++) {
+ st = ic->streams[i];
+ if (st->start_time != AV_NOPTS_VALUE &&
+ st->start_time < start_time)
+ start_time = st->start_time;
+ }
+ if (start_time != MAXINT64)
+ ic->start_time = start_time;
+
+ /* estimate the end time (duration) */
+ /* XXX: may need to support wrapping */
+ filesize = ic->file_size;
+ offset = filesize - DURATION_MAX_READ_SIZE;
+ if (offset < 0)
+ offset = 0;
+
+ /* flush packet queue */
+ flush_packet_queue(ic);
+
+ url_fseek(&ic->pb, offset, SEEK_SET);
+ read_size = 0;
+ for(;;) {
+ if (read_size >= DURATION_MAX_READ_SIZE)
+ break;
+ /* if all info is available, we can stop */
+ for(i = 0;i < ic->nb_streams; i++) {
+ st = ic->streams[i];
+ if (st->duration == AV_NOPTS_VALUE)
+ break;
+ }
+ if (i == ic->nb_streams)
+ break;
+
+ ret = av_read_packet(ic, pkt);
+ if (ret != 0)
+ break;
+ read_size += pkt->size;
+ st = ic->streams[pkt->stream_index];
+ if (pkt->pts != AV_NOPTS_VALUE) {
+ end_time = (int64_t)((double)pkt->pts * ic->pts_num * (double)AV_TIME_BASE / ic->pts_den);
+ duration = end_time - st->start_time;
+ if (duration > 0) {
+ if (st->duration == AV_NOPTS_VALUE ||
+ st->duration < duration)
+ st->duration = duration;
+ }
+ }
+ av_free_packet(pkt);
+ }
+
+ /* estimate total duration */
+ end_time = MININT64;
+ for(i = 0;i < ic->nb_streams; i++) {
+ st = ic->streams[i];
+ if (st->duration != AV_NOPTS_VALUE) {
+ end_time1 = st->start_time + st->duration;
+ if (end_time1 > end_time)
+ end_time = end_time1;
+ }
+ }
+
+ /* update start_time (new stream may have been created, so we do
+ it at the end */
+ if (ic->start_time != AV_NOPTS_VALUE) {
+ for(i = 0; i < ic->nb_streams; i++) {
+ st = ic->streams[i];
+ if (st->start_time == AV_NOPTS_VALUE)
+ st->start_time = ic->start_time;
+ }
+ }
+
+ if (end_time != MININT64) {
+ /* put dummy values for duration if needed */
+ for(i = 0;i < ic->nb_streams; i++) {
+ st = ic->streams[i];
+ if (st->duration == AV_NOPTS_VALUE &&
+ st->start_time != AV_NOPTS_VALUE)
+ st->duration = end_time - st->start_time;
+ }
+ ic->duration = end_time - ic->start_time;
+ }
+
+ url_fseek(&ic->pb, 0, SEEK_SET);
+}
+
+static void av_estimate_timings(AVFormatContext *ic)
+{
+ URLContext *h;
+ int64_t file_size;
+
+ /* get the file size, if possible */
+ if (ic->iformat->flags & AVFMT_NOFILE) {
+ file_size = 0;
+ } else {
+ h = url_fileno(&ic->pb);
+ file_size = url_filesize(h);
+ if (file_size < 0)
+ file_size = 0;
+ }
+ ic->file_size = file_size;
+
+ if (ic->iformat == &mpegps_demux) {
+ /* get accurate estimate from the PTSes */
+ av_estimate_timings_from_pts(ic);
+ } else if (av_has_timings(ic)) {
+ /* at least one components has timings - we use them for all
+ the components */
+ fill_all_stream_timings(ic);
+ } else {
+ /* less precise: use bit rate info */
+ av_estimate_timings_from_bit_rate(ic);
+ }
+ av_update_stream_timings(ic);
+
+#if 0
+ {
+ int i;
+ AVStream *st;
+ for(i = 0;i < ic->nb_streams; i++) {
+ st = ic->streams[i];
+ printf("%d: start_time: %0.3f duration: %0.3f\n",
+ i, (double)st->start_time / AV_TIME_BASE,
+ (double)st->duration / AV_TIME_BASE);
+ }
+ printf("stream: start_time: %0.3f duration: %0.3f bitrate=%d kb/s\n",
+ (double)ic->start_time / AV_TIME_BASE,
+ (double)ic->duration / AV_TIME_BASE,
+ ic->bit_rate / 1000);
+ }
+#endif
+}
+
+/* state for codec information */
+#define CSTATE_NOTFOUND 0
+#define CSTATE_DECODING 1
+#define CSTATE_FOUND 2
+
+static int has_codec_parameters(AVCodecContext *enc)
+{
+ int val;
+ switch(enc->codec_type) {
+ case CODEC_TYPE_AUDIO:
+ val = enc->sample_rate;
+ break;
+ case CODEC_TYPE_VIDEO:
+ val = enc->width;
+ break;
+ default:
+ val = 1;
+ break;
+ }
+ return (val != 0);
+}
+
+/**
+ * Read the beginning of a media file to get stream information. This
+ * is useful for file formats with no headers such as MPEG. This
+ * function also compute the real frame rate in case of mpeg2 repeat
+ * frame mode.
+ *
+ * @param ic media file handle
+ * @return >=0 if OK. AVERROR_xxx if error.
+ */
+int av_find_stream_info(AVFormatContext *ic)
+{
+ int i, count, ret, got_picture, size, read_size;
+ AVCodec *codec;
+ AVStream *st;
+ AVPacket *pkt;
+ AVFrame picture;
+ AVPacketList *pktl=NULL, **ppktl;
+ short samples[AVCODEC_MAX_AUDIO_FRAME_SIZE / 2];
+ uint8_t *ptr;
+ int min_read_size, max_read_size;
+
+ /* typical mpeg ts rate is 40 Mbits. DVD rate is about 10
+ Mbits. We read at most 0.2 second of file to find all streams */
+
+ /* XXX: base it on stream bitrate when possible */
+ if (ic->iformat == &mpegts_demux) {
+ /* maximum number of bytes we accept to read to find all the streams
+ in a file */
+ min_read_size = 6000000;
+ } else {
+ min_read_size = 250000;
+ }
+ /* max read size is 2 seconds of video max */
+ max_read_size = min_read_size * 10;
+
+ /* set initial codec state */
+ for(i=0;i<ic->nb_streams;i++) {
+ st = ic->streams[i];
+ if (has_codec_parameters(&st->codec))
+ st->codec_info_state = CSTATE_FOUND;
+ else
+ st->codec_info_state = CSTATE_NOTFOUND;
+ st->codec_info_nb_repeat_frames = 0;
+ st->codec_info_nb_real_frames = 0;
+ }
+
+ count = 0;
+ read_size = 0;
+ ppktl = &ic->packet_buffer;
+ for(;;) {
+ /* check if one codec still needs to be handled */
+ for(i=0;i<ic->nb_streams;i++) {
+ st = ic->streams[i];
+ if (st->codec_info_state != CSTATE_FOUND)
+ break;
+ }
+ if (i == ic->nb_streams) {
+ /* NOTE: if the format has no header, then we need to read
+ some packets to get most of the streams, so we cannot
+ stop here */
+ if (!(ic->iformat->flags & AVFMT_NOHEADER) ||
+ read_size >= min_read_size) {
+ /* if we found the info for all the codecs, we can stop */
+ ret = count;
+ break;
+ }
+ } else {
+ /* we did not get all the codec info, but we read too much data */
+ if (read_size >= max_read_size) {
+ ret = count;
+ break;
+ }
+ }
+
+ pktl = av_mallocz(sizeof(AVPacketList));
+ if (!pktl) {
+ ret = AVERROR_NOMEM;
+ break;
+ }
+
+ /* add the packet in the buffered packet list */
+ *ppktl = pktl;
+ ppktl = &pktl->next;
+
+ /* NOTE: a new stream can be added there if no header in file
+ (AVFMT_NOHEADER) */
+ pkt = &pktl->pkt;
+ if (ic->iformat->read_packet(ic, pkt) < 0) {
+ /* EOF or error */
+ ret = -1; /* we could not have all the codec parameters before EOF */
+ if ((ic->iformat->flags & AVFMT_NOHEADER) &&
+ i == ic->nb_streams)
+ ret = 0;
+ break;
+ }
+ read_size += pkt->size;
+
+ /* open new codecs */
+ for(i=0;i<ic->nb_streams;i++) {
+ st = ic->streams[i];
+ if (st->codec_info_state == CSTATE_NOTFOUND) {
+ /* set to found in case of error */
+ st->codec_info_state = CSTATE_FOUND;
+ codec = avcodec_find_decoder(st->codec.codec_id);
+ if (codec) {
+ if(codec->capabilities & CODEC_CAP_TRUNCATED)
+ st->codec.flags |= CODEC_FLAG_TRUNCATED;
+
+ ret = avcodec_open(&st->codec, codec);
+ if (ret >= 0)
+ st->codec_info_state = CSTATE_DECODING;
+ }
+ }
+ }
+
+ st = ic->streams[pkt->stream_index];
+ if (st->codec_info_state == CSTATE_DECODING) {
+ /* decode the data and update codec parameters */
+ ptr = pkt->data;
+ size = pkt->size;
+ while (size > 0) {
+ switch(st->codec.codec_type) {
+ case CODEC_TYPE_VIDEO:
+ ret = avcodec_decode_video(&st->codec, &picture,
+ &got_picture, ptr, size);
+ break;
+ case CODEC_TYPE_AUDIO:
+ ret = avcodec_decode_audio(&st->codec, samples,
+ &got_picture, ptr, size);
+ break;
+ default:
+ ret = -1;
+ break;
+ }
+ if (ret < 0) {
+ /* if error, simply ignore because another packet
+ may be OK */
+ break;
+ }
+ if (got_picture) {
+ /* we got the parameters - now we can stop
+ examining this stream */
+ /* XXX: add a codec info so that we can decide if
+ the codec can repeat frames */
+ if (st->codec.codec_id == CODEC_ID_MPEG1VIDEO &&
+ ic->iformat != &mpegts_demux &&
+ st->codec.sub_id == 2) {
+ /* for mpeg2 video, we want to know the real
+ frame rate, so we decode 40 frames. In mpeg
+ TS case we do not do it because it would be
+ too long */
+ st->codec_info_nb_real_frames++;
+ st->codec_info_nb_repeat_frames += st->codec.coded_frame->repeat_pict;
+#if 0
+ /* XXX: testing */
+ if ((st->codec_info_nb_real_frames % 24) == 23) {
+ st->codec_info_nb_repeat_frames += 2;
+ }
+#endif
+ /* stop after 40 frames */
+ if (st->codec_info_nb_real_frames >= 40) {
+ av_reduce(
+ &st->r_frame_rate,
+ &st->r_frame_rate_base,
+ (int64_t)st->codec.frame_rate * st->codec_info_nb_real_frames,
+ (st->codec_info_nb_real_frames + (st->codec_info_nb_repeat_frames >> 1)) * st->codec.frame_rate_base,
+ 1<<30);
+ goto close_codec;
+ }
+ } else {
+ close_codec:
+ st->codec_info_state = CSTATE_FOUND;
+ avcodec_close(&st->codec);
+ break;
+ }
+ }
+ ptr += ret;
+ size -= ret;
+ }
+ }
+ count++;
+ }
+
+ /* close each codec if there are opened */
+ for(i=0;i<ic->nb_streams;i++) {
+ st = ic->streams[i];
+ if (st->codec_info_state == CSTATE_DECODING)
+ avcodec_close(&st->codec);
+ }
+
+ /* set real frame rate info */
+ for(i=0;i<ic->nb_streams;i++) {
+ st = ic->streams[i];
+ if (st->codec.codec_type == CODEC_TYPE_VIDEO) {
+ if (!st->r_frame_rate){
+ st->r_frame_rate = st->codec.frame_rate;
+ st->r_frame_rate_base = st->codec.frame_rate_base;
+ }
+ }
+ }
+
+
+ av_estimate_timings(ic);
+ return ret;
+}
+
+/**
+ * Close a media file (but not its codecs)
+ *
+ * @param s media file handle
+ */
+void av_close_input_file(AVFormatContext *s)
+{
+ int i, must_open_file;
+
+ if (s->iformat->read_close)
+ s->iformat->read_close(s);
+ for(i=0;i<s->nb_streams;i++) {
+ av_free(s->streams[i]);
+ }
+ if (s->packet_buffer) {
+ AVPacketList *p, *p1;
+ p = s->packet_buffer;
+ while (p != NULL) {
+ p1 = p->next;
+ av_free_packet(&p->pkt);
+ av_free(p);
+ p = p1;
+ }
+ s->packet_buffer = NULL;
+ }
+ must_open_file = 1;
+ if ((s->iformat->flags & AVFMT_NOFILE)
+#ifdef CONFIG_NETWORK
+ || (s->iformat == &rtp_demux && !strcmp(s->filename, "null"))
+#endif
+ ) {
+ must_open_file = 0;
+ }
+ if (must_open_file) {
+ url_fclose(&s->pb);
+ }
+ av_freep(&s->priv_data);
+ av_free(s);
+}
+
+/**
+ * Add a new stream to a media file. Can only be called in the
+ * read_header function. If the flag AVFMT_NOHEADER is in the format
+ * description, then new streams can be added in read_packet too.
+ *
+ *
+ * @param s media file handle
+ * @param id file format dependent stream id
+ */
+AVStream *av_new_stream(AVFormatContext *s, int id)
+{
+ AVStream *st;
+
+ if (s->nb_streams >= MAX_STREAMS)
+ return NULL;
+
+ st = av_mallocz(sizeof(AVStream));
+ if (!st)
+ return NULL;
+ avcodec_get_context_defaults(&st->codec);
+ if (s->iformat) {
+ /* no default bitrate if decoding */
+ st->codec.bit_rate = 0;
+ }
+ st->index = s->nb_streams;
+ st->id = id;
+ st->start_time = AV_NOPTS_VALUE;
+ st->duration = AV_NOPTS_VALUE;
+ s->streams[s->nb_streams++] = st;
+ return st;
+}
+
+/************************************************************/
+/* output media file */
+
+int av_set_parameters(AVFormatContext *s, AVFormatParameters *ap)
+{
+ int ret;
+
+ if (s->oformat->priv_data_size > 0) {
+ s->priv_data = av_mallocz(s->oformat->priv_data_size);
+ if (!s->priv_data)
+ return AVERROR_NOMEM;
+ } else
+ s->priv_data = NULL;
+
+ if (s->oformat->set_parameters) {
+ ret = s->oformat->set_parameters(s, ap);
+ if (ret < 0)
+ return ret;
+ }
+ return 0;
+}
+
+/**
+ * allocate the stream private data and write the stream header to an
+ * output media file
+ *
+ * @param s media file handle
+ * @return 0 if OK. AVERROR_xxx if error.
+ */
+int av_write_header(AVFormatContext *s)
+{
+ int ret, i;
+ AVStream *st;
+
+ /* default pts settings is MPEG like */
+ av_set_pts_info(s, 33, 1, 90000);
+ ret = s->oformat->write_header(s);
+ if (ret < 0)
+ return ret;
+
+ /* init PTS generation */
+ for(i=0;i<s->nb_streams;i++) {
+ st = s->streams[i];
+
+ switch (st->codec.codec_type) {
+ case CODEC_TYPE_AUDIO:
+ av_frac_init(&st->pts, 0, 0,
+ (int64_t)s->pts_num * st->codec.sample_rate);
+ break;
+ case CODEC_TYPE_VIDEO:
+ av_frac_init(&st->pts, 0, 0,
+ (int64_t)s->pts_num * st->codec.frame_rate);
+ break;
+ default:
+ break;
+ }
+ }
+ return 0;
+}
+
+/**
+ * Write a packet to an output media file. The packet shall contain
+ * one audio or video frame.
+ *
+ * @param s media file handle
+ * @param stream_index stream index
+ * @param buf buffer containing the frame data
+ * @param size size of buffer
+ * @return < 0 if error, = 0 if OK, 1 if end of stream wanted.
+ */
+int av_write_frame(AVFormatContext *s, int stream_index, const uint8_t *buf,
+ int size)
+{
+ AVStream *st;
+ int64_t pts_mask;
+ int ret, frame_size;
+
+ st = s->streams[stream_index];
+ pts_mask = (1LL << s->pts_wrap_bits) - 1;
+ ret = s->oformat->write_packet(s, stream_index, (uint8_t *)buf, size,
+ st->pts.val & pts_mask);
+ if (ret < 0)
+ return ret;
+
+ /* update pts */
+ switch (st->codec.codec_type) {
+ case CODEC_TYPE_AUDIO:
+ if (st->codec.frame_size <= 1) {
+ frame_size = size / st->codec.channels;
+ /* specific hack for pcm codecs because no frame size is provided */
+ switch(st->codec.codec_id) {
+ case CODEC_ID_PCM_S16LE:
+ case CODEC_ID_PCM_S16BE:
+ case CODEC_ID_PCM_U16LE:
+ case CODEC_ID_PCM_U16BE:
+ frame_size >>= 1;
+ break;
+ default:
+ break;
+ }
+ } else {
+ frame_size = st->codec.frame_size;
+ }
+ av_frac_add(&st->pts,
+ (int64_t)s->pts_den * frame_size);
+ break;
+ case CODEC_TYPE_VIDEO:
+ av_frac_add(&st->pts,
+ (int64_t)s->pts_den * st->codec.frame_rate_base);
+ break;
+ default:
+ break;
+ }
+ return ret;
+}
+
+/**
+ * write the stream trailer to an output media file and and free the
+ * file private data.
+ *
+ * @param s media file handle
+ * @return 0 if OK. AVERROR_xxx if error. */
+int av_write_trailer(AVFormatContext *s)
+{
+ int ret;
+ ret = s->oformat->write_trailer(s);
+ av_freep(&s->priv_data);
+ return ret;
+}
+
+/* "user interface" functions */
+
+void dump_format(AVFormatContext *ic,
+ int index,
+ const char *url,
+ int is_output)
+{
+ int i, flags;
+ char buf[256];
+
+ fprintf(stderr, "%s #%d, %s, %s '%s':\n",
+ is_output ? "Output" : "Input",
+ index,
+ is_output ? ic->oformat->name : ic->iformat->name,
+ is_output ? "to" : "from", url);
+ if (!is_output) {
+ fprintf(stderr, " Duration: ");
+ if (ic->duration != AV_NOPTS_VALUE) {
+ int hours, mins, secs, us;
+ secs = ic->duration / AV_TIME_BASE;
+ us = ic->duration % AV_TIME_BASE;
+ mins = secs / 60;
+ secs %= 60;
+ hours = mins / 60;
+ mins %= 60;
+ fprintf(stderr, "%02d:%02d:%02d.%01d", hours, mins, secs,
+ (10 * us) / AV_TIME_BASE);
+ } else {
+ fprintf(stderr, "N/A");
+ }
+ fprintf(stderr, ", bitrate: ");
+ if (ic->bit_rate) {
+ fprintf(stderr,"%d kb/s", ic->bit_rate / 1000);
+ } else {
+ fprintf(stderr, "N/A");
+ }
+ fprintf(stderr, "\n");
+ }
+ for(i=0;i<ic->nb_streams;i++) {
+ AVStream *st = ic->streams[i];
+ avcodec_string(buf, sizeof(buf), &st->codec, is_output);
+ fprintf(stderr, " Stream #%d.%d", index, i);
+ /* the pid is an important information, so we display it */
+ /* XXX: add a generic system */
+ if (is_output)
+ flags = ic->oformat->flags;
+ else
+ flags = ic->iformat->flags;
+ if (flags & AVFMT_SHOW_IDS) {
+ fprintf(stderr, "[0x%x]", st->id);
+ }
+ fprintf(stderr, ": %s\n", buf);
+ }
+}
+
+typedef struct {
+ const char *abv;
+ int width, height;
+ int frame_rate, frame_rate_base;
+} AbvEntry;
+
+static AbvEntry frame_abvs[] = {
+ { "ntsc", 720, 480, 30000, 1001 },
+ { "pal", 720, 576, 25, 1 },
+ { "qntsc", 352, 240, 30000, 1001 }, /* VCD compliant ntsc */
+ { "qpal", 352, 288, 25, 1 }, /* VCD compliant pal */
+ { "sntsc", 640, 480, 30000, 1001 }, /* square pixel ntsc */
+ { "spal", 768, 576, 25, 1 }, /* square pixel pal */
+ { "film", 352, 240, 24, 1 },
+ { "ntsc-film", 352, 240, 24000, 1001 },
+ { "sqcif", 128, 96, 0, 0 },
+ { "qcif", 176, 144, 0, 0 },
+ { "cif", 352, 288, 0, 0 },
+ { "4cif", 704, 576, 0, 0 },
+};
+
+int parse_image_size(int *width_ptr, int *height_ptr, const char *str)
+{
+ int i;
+ int n = sizeof(frame_abvs) / sizeof(AbvEntry);
+ const char *p;
+ int frame_width = 0, frame_height = 0;
+
+ for(i=0;i<n;i++) {
+ if (!strcmp(frame_abvs[i].abv, str)) {
+ frame_width = frame_abvs[i].width;
+ frame_height = frame_abvs[i].height;
+ break;
+ }
+ }
+ if (i == n) {
+ p = str;
+ frame_width = strtol(p, (char **)&p, 10);
+ if (*p)
+ p++;
+ frame_height = strtol(p, (char **)&p, 10);
+ }
+ if (frame_width <= 0 || frame_height <= 0)
+ return -1;
+ *width_ptr = frame_width;
+ *height_ptr = frame_height;
+ return 0;
+}
+
+int parse_frame_rate(int *frame_rate, int *frame_rate_base, const char *arg)
+{
+ int i;
+ char* cp;
+
+ /* First, we check our abbreviation table */
+ for (i = 0; i < sizeof(frame_abvs)/sizeof(*frame_abvs); ++i)
+ if (!strcmp(frame_abvs[i].abv, arg)) {
+ *frame_rate = frame_abvs[i].frame_rate;
+ *frame_rate_base = frame_abvs[i].frame_rate_base;
+ return 0;
+ }
+
+ /* Then, we try to parse it as fraction */
+ cp = strchr(arg, '/');
+ if (cp) {
+ char* cpp;
+ *frame_rate = strtol(arg, &cpp, 10);
+ if (cpp != arg || cpp == cp)
+ *frame_rate_base = strtol(cp+1, &cpp, 10);
+ else
+ *frame_rate = 0;
+ }
+ else {
+ /* Finally we give up and parse it as double */
+ *frame_rate_base = DEFAULT_FRAME_RATE_BASE;
+ *frame_rate = (int)(strtod(arg, 0) * (*frame_rate_base) + 0.5);
+ }
+ if (!*frame_rate || !*frame_rate_base)
+ return -1;
+ else
+ return 0;
+}
+
+/* Syntax:
+ * - If not a duration:
+ * [{YYYY-MM-DD|YYYYMMDD}]{T| }{HH[:MM[:SS[.m...]]][Z]|HH[MM[SS[.m...]]][Z]}
+ * Time is localtime unless Z is suffixed to the end. In this case GMT
+ * Return the date in micro seconds since 1970
+ * - If duration:
+ * HH[:MM[:SS[.m...]]]
+ * S+[.m...]
+ */
+int64_t parse_date(const char *datestr, int duration)
+{
+ const char *p;
+ int64_t t;
+ struct tm dt;
+ int i;
+ static const char *date_fmt[] = {
+ "%Y-%m-%d",
+ "%Y%m%d",
+ };
+ static const char *time_fmt[] = {
+ "%H:%M:%S",
+ "%H%M%S",
+ };
+ const char *q;
+ int is_utc, len;
+ char lastch;
+ time_t now = time(0);
+
+ len = strlen(datestr);
+ if (len > 0)
+ lastch = datestr[len - 1];
+ else
+ lastch = '\0';
+ is_utc = (lastch == 'z' || lastch == 'Z');
+
+ memset(&dt, 0, sizeof(dt));
+
+ p = datestr;
+ q = NULL;
+ if (!duration) {
+ for (i = 0; i < sizeof(date_fmt) / sizeof(date_fmt[0]); i++) {
+ q = small_strptime(p, date_fmt[i], &dt);
+ if (q) {
+ break;
+ }
+ }
+
+ if (!q) {
+ if (is_utc) {
+ dt = *gmtime(&now);
+ } else {
+ dt = *localtime(&now);
+ }
+ dt.tm_hour = dt.tm_min = dt.tm_sec = 0;
+ } else {
+ p = q;
+ }
+
+ if (*p == 'T' || *p == 't' || *p == ' ')
+ p++;
+
+ for (i = 0; i < sizeof(time_fmt) / sizeof(time_fmt[0]); i++) {
+ q = small_strptime(p, time_fmt[i], &dt);
+ if (q) {
+ break;
+ }
+ }
+ } else {
+ q = small_strptime(p, time_fmt[0], &dt);
+ if (!q) {
+ dt.tm_sec = strtol(p, (char **)&q, 10);
+ dt.tm_min = 0;
+ dt.tm_hour = 0;
+ }
+ }
+
+ /* Now we have all the fields that we can get */
+ if (!q) {
+ if (duration)
+ return 0;
+ else
+ return now * int64_t_C(1000000);
+ }
+
+ if (duration) {
+ t = dt.tm_hour * 3600 + dt.tm_min * 60 + dt.tm_sec;
+ } else {
+ dt.tm_isdst = -1; /* unknown */
+ if (is_utc) {
+ t = mktimegm(&dt);
+ } else {
+ t = mktime(&dt);
+ }
+ }
+
+ t *= 1000000;
+
+ if (*q == '.') {
+ int val, n;
+ q++;
+ for (val = 0, n = 100000; n >= 1; n /= 10, q++) {
+ if (!isdigit(*q))
+ break;
+ val += n * (*q - '0');
+ }
+ t += val;
+ }
+ return t;
+}
+
+/* syntax: '?tag1=val1&tag2=val2...'. Little URL decoding is done. Return
+ 1 if found */
+int find_info_tag(char *arg, int arg_size, const char *tag1, const char *info)
+{
+ const char *p;
+ char tag[128], *q;
+
+ p = info;
+ if (*p == '?')
+ p++;
+ for(;;) {
+ q = tag;
+ while (*p != '\0' && *p != '=' && *p != '&') {
+ if ((q - tag) < sizeof(tag) - 1)
+ *q++ = *p;
+ p++;
+ }
+ *q = '\0';
+ q = arg;
+ if (*p == '=') {
+ p++;
+ while (*p != '&' && *p != '\0') {
+ if ((q - arg) < arg_size - 1) {
+ if (*p == '+')
+ *q++ = ' ';
+ else
+ *q++ = *p;
+ }
+ p++;
+ }
+ *q = '\0';
+ }
+ if (!strcmp(tag, tag1))
+ return 1;
+ if (*p != '&')
+ break;
+ p++;
+ }
+ return 0;
+}
+
+/* Return in 'buf' the path with '%d' replaced by number. Also handles
+ the '%0nd' format where 'n' is the total number of digits and
+ '%%'. Return 0 if OK, and -1 if format error */
+int get_frame_filename(char *buf, int buf_size,
+ const char *path, int number)
+{
+ const char *p;
+ char *q, buf1[20];
+ int nd, len, c, percentd_found;
+
+ q = buf;
+ p = path;
+ percentd_found = 0;
+ for(;;) {
+ c = *p++;
+ if (c == '\0')
+ break;
+ if (c == '%') {
+ do {
+ nd = 0;
+ while (isdigit(*p)) {
+ nd = nd * 10 + *p++ - '0';
+ }
+ c = *p++;
+ } while (isdigit(c));
+
+ switch(c) {
+ case '%':
+ goto addchar;
+ case 'd':
+ if (percentd_found)
+ goto fail;
+ percentd_found = 1;
+ snprintf(buf1, sizeof(buf1), "%0*d", nd, number);
+ len = strlen(buf1);
+ if ((q - buf + len) > buf_size - 1)
+ goto fail;
+ memcpy(q, buf1, len);
+ q += len;
+ break;
+ default:
+ goto fail;
+ }
+ } else {
+ addchar:
+ if ((q - buf) < buf_size - 1)
+ *q++ = c;
+ }
+ }
+ if (!percentd_found)
+ goto fail;
+ *q = '\0';
+ return 0;
+ fail:
+ *q = '\0';
+ return -1;
+}
+
+/**
+ *
+ * Print on stdout a nice hexa dump of a buffer
+ * @param buf buffer
+ * @param size buffer size
+ */
+void av_hex_dump(uint8_t *buf, int size)
+{
+ int len, i, j, c;
+
+ for(i=0;i<size;i+=16) {
+ len = size - i;
+ if (len > 16)
+ len = 16;
+ printf("%08x ", i);
+ for(j=0;j<16;j++) {
+ if (j < len)
+ printf(" %02x", buf[i+j]);
+ else
+ printf(" ");
+ }
+ printf(" ");
+ for(j=0;j<len;j++) {
+ c = buf[i+j];
+ if (c < ' ' || c > '~')
+ c = '.';
+ printf("%c", c);
+ }
+ printf("\n");
+ }
+}
+
+void url_split(char *proto, int proto_size,
+ char *hostname, int hostname_size,
+ int *port_ptr,
+ char *path, int path_size,
+ const char *url)
+{
+ const char *p;
+ char *q;
+ int port;
+
+ port = -1;
+
+ p = url;
+ q = proto;
+ while (*p != ':' && *p != '\0') {
+ if ((q - proto) < proto_size - 1)
+ *q++ = *p;
+ p++;
+ }
+ if (proto_size > 0)
+ *q = '\0';
+ if (*p == '\0') {
+ if (proto_size > 0)
+ proto[0] = '\0';
+ if (hostname_size > 0)
+ hostname[0] = '\0';
+ p = url;
+ } else {
+ p++;
+ if (*p == '/')
+ p++;
+ if (*p == '/')
+ p++;
+ q = hostname;
+ while (*p != ':' && *p != '/' && *p != '?' && *p != '\0') {
+ if ((q - hostname) < hostname_size - 1)
+ *q++ = *p;
+ p++;
+ }
+ if (hostname_size > 0)
+ *q = '\0';
+ if (*p == ':') {
+ p++;
+ port = strtoul(p, (char **)&p, 10);
+ }
+ }
+ if (port_ptr)
+ *port_ptr = port;
+ pstrcpy(path, path_size, p);
+}
+
+/**
+ * Set the pts for a given stream
+ * @param s stream
+ * @param pts_wrap_bits number of bits effectively used by the pts
+ * (used for wrap control, 33 is the value for MPEG)
+ * @param pts_num numerator to convert to seconds (MPEG: 1)
+ * @param pts_den denominator to convert to seconds (MPEG: 90000)
+ */
+void av_set_pts_info(AVFormatContext *s, int pts_wrap_bits,
+ int pts_num, int pts_den)
+{
+ s->pts_wrap_bits = pts_wrap_bits;
+ s->pts_num = pts_num;
+ s->pts_den = pts_den;
+}
+
+/* fraction handling */
+
+/**
+ * f = val + (num / den) + 0.5. 'num' is normalized so that it is such
+ * as 0 <= num < den.
+ *
+ * @param f fractional number
+ * @param val integer value
+ * @param num must be >= 0
+ * @param den must be >= 1
+ */
+void av_frac_init(AVFrac *f, int64_t val, int64_t num, int64_t den)
+{
+ num += (den >> 1);
+ if (num >= den) {
+ val += num / den;
+ num = num % den;
+ }
+ f->val = val;
+ f->num = num;
+ f->den = den;
+}
+
+/* set f to (val + 0.5) */
+void av_frac_set(AVFrac *f, int64_t val)
+{
+ f->val = val;
+ f->num = f->den >> 1;
+}
+
+/**
+ * Fractionnal addition to f: f = f + (incr / f->den)
+ *
+ * @param f fractional number
+ * @param incr increment, can be positive or negative
+ */
+void av_frac_add(AVFrac *f, int64_t incr)
+{
+ int64_t num, den;
+
+ num = f->num + incr;
+ den = f->den;
+ if (num < 0) {
+ f->val += num / den;
+ num = num % den;
+ if (num < 0) {
+ num += den;
+ f->val--;
+ }
+ } else if (num >= den) {
+ f->val += num / den;
+ num = num % den;
+ }
+ f->num = num;
+}
+
+/**
+ * register a new image format
+ * @param img_fmt Image format descriptor
+ */
+void av_register_image_format(AVImageFormat *img_fmt)
+{
+ AVImageFormat **p;
+
+ p = &first_image_format;
+ while (*p != NULL) p = &(*p)->next;
+ *p = img_fmt;
+ img_fmt->next = NULL;
+}
+
+/* guess image format */
+AVImageFormat *av_probe_image_format(AVProbeData *pd)
+{
+ AVImageFormat *fmt1, *fmt;
+ int score, score_max;
+
+ fmt = NULL;
+ score_max = 0;
+ for(fmt1 = first_image_format; fmt1 != NULL; fmt1 = fmt1->next) {
+ if (fmt1->img_probe) {
+ score = fmt1->img_probe(pd);
+ if (score > score_max) {
+ score_max = score;
+ fmt = fmt1;
+ }
+ }
+ }
+ return fmt;
+}
+
+AVImageFormat *guess_image_format(const char *filename)
+{
+ AVImageFormat *fmt1;
+
+ for(fmt1 = first_image_format; fmt1 != NULL; fmt1 = fmt1->next) {
+ if (fmt1->extensions && match_ext(filename, fmt1->extensions))
+ return fmt1;
+ }
+ return NULL;
+}
+
+/**
+ * Read an image from a stream.
+ * @param gb byte stream containing the image
+ * @param fmt image format, NULL if probing is required
+ */
+int av_read_image(ByteIOContext *pb, const char *filename,
+ AVImageFormat *fmt,
+ int (*alloc_cb)(void *, AVImageInfo *info), void *opaque)
+{
+ char buf[PROBE_BUF_SIZE];
+ AVProbeData probe_data, *pd = &probe_data;
+ offset_t pos;
+ int ret;
+
+ if (!fmt) {
+ pd->filename = filename;
+ pd->buf = buf;
+ pos = url_ftell(pb);
+ pd->buf_size = get_buffer(pb, buf, PROBE_BUF_SIZE);
+ url_fseek(pb, pos, SEEK_SET);
+ fmt = av_probe_image_format(pd);
+ }
+ if (!fmt)
+ return AVERROR_NOFMT;
+ ret = fmt->img_read(pb, alloc_cb, opaque);
+ return ret;
+}
+
+/**
+ * Write an image to a stream.
+ * @param pb byte stream for the image output
+ * @param fmt image format
+ * @param img image data and informations
+ */
+int av_write_image(ByteIOContext *pb, AVImageFormat *fmt, AVImageInfo *img)
+{
+ return fmt->img_write(pb, img);
+}
+