summaryrefslogtreecommitdiff
path: root/libav/ffm.c
diff options
context:
space:
mode:
Diffstat (limited to 'libav/ffm.c')
-rw-r--r--libav/ffm.c599
1 files changed, 599 insertions, 0 deletions
diff --git a/libav/ffm.c b/libav/ffm.c
new file mode 100644
index 0000000000..76e7613286
--- /dev/null
+++ b/libav/ffm.c
@@ -0,0 +1,599 @@
+/*
+ * FFM (ffserver live feed) encoder and decoder
+ * Copyright (c) 2001 Gerard Lantau.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+#include <stdlib.h>
+#include <stdio.h>
+#include <errno.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "avformat.h"
+
+/* The FFM file is made of blocks of fixed size */
+#define FFM_HEADER_SIZE 14
+#define PACKET_ID 0x666d
+
+/* each packet contains frames (which can span several packets */
+#define FRAME_HEADER_SIZE 5
+#define FLAG_KEY_FRAME 0x01
+
+typedef struct FFMStream {
+ INT64 pts;
+} FFMStream;
+
+enum {
+ READ_HEADER,
+ READ_DATA,
+};
+
+typedef struct FFMContext {
+ /* only reading mode */
+ offset_t write_index, file_size;
+ int read_state;
+ UINT8 header[FRAME_HEADER_SIZE];
+
+ /* read and write */
+ int first_packet; /* true if first packet, needed to set the discontinuity tag */
+ int packet_size;
+ int frame_offset;
+ INT64 pts;
+ UINT8 *packet_ptr, *packet_end;
+ UINT8 packet[1]; /* must be last */
+} FFMContext;
+
+static void flush_packet(AVFormatContext *s)
+{
+ FFMContext *ffm = s->priv_data;
+ int fill_size, h;
+ ByteIOContext *pb = &s->pb;
+
+ fill_size = ffm->packet_end - ffm->packet_ptr;
+ memset(ffm->packet_ptr, 0, fill_size);
+
+ /* put header */
+ put_be16(pb, PACKET_ID);
+ put_be16(pb, fill_size);
+ put_be64(pb, ffm->pts);
+ h = ffm->frame_offset;
+ if (ffm->first_packet)
+ h |= 0x8000;
+ put_be16(pb, h);
+ put_buffer(pb, ffm->packet, ffm->packet_end - ffm->packet);
+
+ /* prepare next packet */
+ ffm->frame_offset = 0; /* no key frame */
+ ffm->pts = 0; /* no pts */
+ ffm->packet_ptr = ffm->packet;
+ ffm->first_packet = 0;
+}
+
+/* 'first' is true if first data of a frame */
+static void ffm_write_data(AVFormatContext *s,
+ UINT8 *buf, int size,
+ INT64 pts, int first)
+{
+ FFMContext *ffm = s->priv_data;
+ int len;
+
+ if (first && ffm->frame_offset == 0)
+ ffm->frame_offset = ffm->packet_ptr - ffm->packet + FFM_HEADER_SIZE;
+ if (first && ffm->pts == 0)
+ ffm->pts = pts;
+
+ /* write as many packets as needed */
+ while (size > 0) {
+ len = ffm->packet_end - ffm->packet_ptr;
+ if (len > size)
+ len = size;
+ memcpy(ffm->packet_ptr, buf, len);
+
+ ffm->packet_ptr += len;
+ buf += len;
+ size -= len;
+ if (ffm->packet_ptr >= ffm->packet_end) {
+ /* special case : no pts in packet : we leave the current one */
+ if (ffm->pts == 0)
+ ffm->pts = pts;
+
+ flush_packet(s);
+ }
+ }
+}
+
+static int ffm_write_header(AVFormatContext *s)
+{
+ AVStream *st;
+ FFMStream *fst;
+ FFMContext *ffm;
+ ByteIOContext *pb = &s->pb;
+ AVCodecContext *codec;
+ int bit_rate, i;
+
+ ffm = av_mallocz(sizeof(FFMContext) + FFM_PACKET_SIZE);
+ if (!ffm)
+ return -1;
+
+ s->priv_data = ffm;
+ ffm->packet_size = FFM_PACKET_SIZE;
+
+ /* header */
+ put_tag(pb, "FFM1");
+ put_be32(pb, ffm->packet_size);
+ /* XXX: store write position in other file ? */
+ put_be64(pb, ffm->packet_size); /* current write position */
+
+ put_be32(pb, s->nb_streams);
+ bit_rate = 0;
+ for(i=0;i<s->nb_streams;i++) {
+ st = s->streams[i];
+ bit_rate += st->codec.bit_rate;
+ }
+ put_be32(pb, bit_rate);
+
+ /* list of streams */
+ for(i=0;i<s->nb_streams;i++) {
+ st = s->streams[i];
+ fst = av_mallocz(sizeof(FFMStream) + ffm->packet_size);
+ if (!fst)
+ goto fail;
+ st->priv_data = fst;
+
+ codec = &st->codec;
+ /* generic info */
+ put_be32(pb, codec->codec_id);
+ put_byte(pb, codec->codec_type);
+ put_be32(pb, codec->bit_rate);
+ /* specific info */
+ switch(codec->codec_type) {
+ case CODEC_TYPE_VIDEO:
+ put_be32(pb, (codec->frame_rate * 1000) / FRAME_RATE_BASE);
+ put_be16(pb, codec->width);
+ put_be16(pb, codec->height);
+ break;
+ case CODEC_TYPE_AUDIO:
+ put_be32(pb, codec->sample_rate);
+ put_le16(pb, codec->channels);
+ break;
+ }
+ /* hack to have real time */
+ fst->pts = gettime();
+ }
+
+ /* flush until end of block reached */
+ while ((url_ftell(pb) % ffm->packet_size) != 0)
+ put_byte(pb, 0);
+
+ put_flush_packet(pb);
+
+ /* init packet mux */
+ ffm->packet_ptr = ffm->packet;
+ ffm->packet_end = ffm->packet + ffm->packet_size - FFM_HEADER_SIZE;
+ ffm->frame_offset = 0;
+ ffm->pts = 0;
+ ffm->first_packet = 1;
+
+ return 0;
+ fail:
+ for(i=0;i<s->nb_streams;i++) {
+ st = s->streams[i];
+ fst = st->priv_data;
+ if (fst)
+ free(fst);
+ }
+ free(ffm);
+ return -1;
+}
+
+static int ffm_write_packet(AVFormatContext *s, int stream_index,
+ UINT8 *buf, int size)
+{
+ AVStream *st = s->streams[stream_index];
+ FFMStream *fst = st->priv_data;
+ INT64 pts;
+ UINT8 header[FRAME_HEADER_SIZE];
+
+ pts = fst->pts;
+ /* packet size & key_frame */
+ header[0] = stream_index;
+ header[1] = 0;
+ if (st->codec.key_frame)
+ header[1] |= FLAG_KEY_FRAME;
+ header[2] = (size >> 16) & 0xff;
+ header[3] = (size >> 8) & 0xff;
+ header[4] = size & 0xff;
+ ffm_write_data(s, header, FRAME_HEADER_SIZE, pts, 1);
+ ffm_write_data(s, buf, size, pts, 0);
+
+ if (st->codec.codec_type == CODEC_TYPE_AUDIO) {
+ fst->pts += (INT64)((float)st->codec.frame_size / st->codec.sample_rate * 1000000.0);
+ } else {
+ fst->pts += (INT64)(1000000.0 * FRAME_RATE_BASE / (float)st->codec.frame_rate);
+ }
+ return 0;
+}
+
+static int ffm_write_trailer(AVFormatContext *s)
+{
+ ByteIOContext *pb = &s->pb;
+ FFMContext *ffm = s->priv_data;
+ int i;
+
+ /* flush packets */
+ if (ffm->packet_ptr > ffm->packet)
+ flush_packet(s);
+
+ put_flush_packet(pb);
+
+ for(i=0;i<s->nb_streams;i++)
+ free(s->streams[i]->priv_data);
+ free(ffm);
+ return 0;
+}
+
+/* ffm demux */
+
+static int ffm_is_avail_data(AVFormatContext *s, int size)
+{
+ FFMContext *ffm = s->priv_data;
+ offset_t pos, avail_size;
+ int len;
+
+ len = ffm->packet_end - ffm->packet_ptr;
+ if (size <= len)
+ return 1;
+ pos = url_ftell(&s->pb);
+ if (pos == ffm->write_index) {
+ /* exactly at the end of stream */
+ return 0;
+ } else if (pos < ffm->write_index) {
+ avail_size = ffm->write_index - pos;
+ } else {
+ avail_size = (ffm->file_size - pos) + (ffm->write_index - FFM_PACKET_SIZE);
+ }
+ avail_size = (avail_size / ffm->packet_size) * (ffm->packet_size - FFM_HEADER_SIZE) + len;
+ if (size <= avail_size)
+ return 1;
+ else
+ return 0;
+}
+
+/* first is true if we read the frame header */
+static int ffm_read_data(AVFormatContext *s,
+ UINT8 *buf, int size, int first)
+{
+ FFMContext *ffm = s->priv_data;
+ ByteIOContext *pb = &s->pb;
+ int len, fill_size, size1, frame_offset;
+
+ size1 = size;
+ while (size > 0) {
+ redo:
+ len = ffm->packet_end - ffm->packet_ptr;
+ if (len > size)
+ len = size;
+ if (len == 0) {
+ if (url_ftell(pb) == ffm->file_size)
+ url_fseek(pb, ffm->packet_size, SEEK_SET);
+ get_be16(pb); /* PACKET_ID */
+ fill_size = get_be16(pb);
+ ffm->pts = get_be64(pb);
+ frame_offset = get_be16(pb);
+ get_buffer(pb, ffm->packet, ffm->packet_size - FFM_HEADER_SIZE);
+ ffm->packet_end = ffm->packet + (ffm->packet_size - FFM_HEADER_SIZE - fill_size);
+ /* if first packet or resynchronization packet, we must
+ handle it specifically */
+ if (ffm->first_packet || (frame_offset & 0x8000)) {
+ ffm->first_packet = 0;
+ ffm->packet_ptr = ffm->packet + (frame_offset & 0x7fff) - FFM_HEADER_SIZE;
+ if (!first)
+ break;
+ } else {
+ ffm->packet_ptr = ffm->packet;
+ }
+ goto redo;
+ }
+ memcpy(buf, ffm->packet_ptr, len);
+ buf += len;
+ ffm->packet_ptr += len;
+ size -= len;
+ first = 0;
+ }
+ return size1 - size;
+}
+
+
+static int ffm_read_header(AVFormatContext *s, AVFormatParameters *ap)
+{
+ AVStream *st;
+ FFMStream *fst;
+ FFMContext *ffm;
+ ByteIOContext *pb = &s->pb;
+ AVCodecContext *codec;
+ int i;
+ UINT32 tag;
+
+ ffm = av_mallocz(sizeof(FFMContext) + FFM_PACKET_SIZE);
+ if (!ffm)
+ return -1;
+
+ s->priv_data = ffm;
+
+ /* header */
+ tag = get_le32(pb);
+ if (tag != MKTAG('F', 'F', 'M', '1'))
+ goto fail;
+ ffm->packet_size = get_be32(pb);
+ if (ffm->packet_size != FFM_PACKET_SIZE)
+ goto fail;
+ ffm->write_index = get_be64(pb);
+ /* get also filesize */
+ if (!url_is_streamed(pb)) {
+ ffm->file_size = url_filesize(url_fileno(pb));
+ } else {
+ ffm->file_size = (1ULL << 63) - 1;
+ }
+
+ s->nb_streams = get_be32(pb);
+ get_be32(pb); /* total bitrate */
+ /* read each stream */
+ for(i=0;i<s->nb_streams;i++) {
+ st = av_mallocz(sizeof(AVStream));
+ if (!st)
+ goto fail;
+ s->streams[i] = st;
+ fst = av_mallocz(sizeof(FFMStream) + ffm->packet_size);
+ if (!fst)
+ goto fail;
+ st->priv_data = fst;
+
+ codec = &st->codec;
+ /* generic info */
+ st->codec.codec_id = get_be32(pb);
+ st->codec.codec_type = get_byte(pb); /* codec_type */
+ codec->bit_rate = get_be32(pb);
+ /* specific info */
+ switch(codec->codec_type) {
+ case CODEC_TYPE_VIDEO:
+ codec->frame_rate = ((INT64)get_be32(pb) * FRAME_RATE_BASE) / 1000;
+ codec->width = get_be16(pb);
+ codec->height = get_be16(pb);
+ break;
+ case CODEC_TYPE_AUDIO:
+ codec->sample_rate = get_be32(pb);
+ codec->channels = get_le16(pb);
+ break;
+ }
+
+ }
+
+ /* get until end of block reached */
+ while ((url_ftell(pb) % ffm->packet_size) != 0)
+ get_byte(pb);
+
+ /* init packet demux */
+ ffm->packet_ptr = ffm->packet;
+ ffm->packet_end = ffm->packet;
+ ffm->frame_offset = 0;
+ ffm->pts = 0;
+ ffm->read_state = READ_HEADER;
+ ffm->first_packet = 1;
+ return 0;
+ fail:
+ for(i=0;i<s->nb_streams;i++) {
+ st = s->streams[i];
+ if (st) {
+ fst = st->priv_data;
+ if (fst)
+ free(fst);
+ free(st);
+ }
+ }
+ if (ffm)
+ free(ffm);
+ return -1;
+}
+
+/* return < 0 if eof */
+static int ffm_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+ int size;
+ FFMContext *ffm = s->priv_data;
+
+ switch(ffm->read_state) {
+ case READ_HEADER:
+ if (!ffm_is_avail_data(s, FRAME_HEADER_SIZE))
+ return -EAGAIN;
+#if 0
+ printf("pos=%08Lx spos=%Lx, write_index=%Lx size=%Lx\n",
+ url_ftell(&s->pb), s->pb.pos, ffm->write_index, ffm->file_size);
+#endif
+ if (ffm_read_data(s, ffm->header, FRAME_HEADER_SIZE, 1) != FRAME_HEADER_SIZE)
+ return -EAGAIN;
+
+#if 0
+ {
+ int i;
+ for(i=0;i<FRAME_HEADER_SIZE;i++)
+ printf("%02x ", ffm->header[i]);
+ printf("\n");
+ }
+#endif
+ ffm->read_state = READ_DATA;
+ /* fall thru */
+ case READ_DATA:
+ size = (ffm->header[2] << 16) | (ffm->header[3] << 8) | ffm->header[4];
+ if (!ffm_is_avail_data(s, size)) {
+ return -EAGAIN;
+ }
+
+ av_new_packet(pkt, size);
+ pkt->stream_index = ffm->header[0];
+ if (ffm->header[1] & FLAG_KEY_FRAME)
+ pkt->flags |= PKT_FLAG_KEY;
+
+ ffm->read_state = READ_HEADER;
+ if (ffm_read_data(s, pkt->data, size, 0) != size) {
+ /* bad case: desynchronized packet. we cancel all the packet loading */
+ av_free_packet(pkt);
+ return -EAGAIN;
+ }
+ break;
+ }
+ return 0;
+}
+
+//#define DEBUG_SEEK
+
+/* pos is between 0 and file_size - FFM_PACKET_SIZE. It is translated
+ by the write position inside this function */
+static void ffm_seek1(AVFormatContext *s, offset_t pos1)
+{
+ FFMContext *ffm = s->priv_data;
+ ByteIOContext *pb = &s->pb;
+ offset_t pos;
+
+ pos = pos1 + ffm->write_index;
+ if (pos >= ffm->file_size)
+ pos -= (ffm->file_size - FFM_PACKET_SIZE);
+#ifdef DEBUG_SEEK
+ printf("seek to %Lx -> %Lx\n", pos1, pos);
+#endif
+ url_fseek(pb, pos, SEEK_SET);
+}
+
+static INT64 get_pts(AVFormatContext *s, offset_t pos)
+{
+ ByteIOContext *pb = &s->pb;
+ INT64 pts;
+
+ ffm_seek1(s, pos);
+ url_fskip(pb, 4);
+ pts = get_be64(pb);
+#ifdef DEBUG_SEEK
+ printf("pts=%0.6f\n", pts / 1000000.0);
+#endif
+ return pts;
+}
+
+/* seek to a given time in the file. The file read pointer is
+ positionned at or before pts. XXX: the following code is quite
+ approximative */
+static int ffm_seek(AVFormatContext *s, INT64 wanted_pts)
+{
+ FFMContext *ffm = s->priv_data;
+ offset_t pos_min, pos_max, pos;
+ INT64 pts_min, pts_max, pts;
+ double pos1;
+
+#ifdef DEBUG_SEEK
+ printf("wanted_pts=%0.6f\n", wanted_pts / 1000000.0);
+#endif
+ /* find the position using linear interpolation (better than
+ dichotomy in typical cases) */
+ pos_min = 0;
+ pos_max = ffm->file_size - 2 * FFM_PACKET_SIZE;
+ while (pos_min <= pos_max) {
+ pts_min = get_pts(s, pos_min);
+ pts_max = get_pts(s, pos_max);
+ /* linear interpolation */
+ pos1 = (double)(pos_max - pos_min) * (double)(wanted_pts - pts_min) /
+ (double)(pts_max - pts_min);
+ pos = (((INT64)pos1) / FFM_PACKET_SIZE) * FFM_PACKET_SIZE;
+ if (pos <= pos_min)
+ pos = pos_min;
+ else if (pos >= pos_max)
+ pos = pos_max;
+ pts = get_pts(s, pos);
+ /* check if we are lucky */
+ if (pts == wanted_pts) {
+ goto found;
+ } else if (pts > wanted_pts) {
+ pos_max = pos - FFM_PACKET_SIZE;
+ } else {
+ pos_min = pos + FFM_PACKET_SIZE;
+ }
+ }
+ pos = pos_min;
+ if (pos > 0)
+ pos -= FFM_PACKET_SIZE;
+ found:
+ ffm_seek1(s, pos);
+ return 0;
+}
+
+offset_t ffm_read_write_index(int fd)
+{
+ UINT8 buf[8];
+ offset_t pos;
+ int i;
+
+ lseek(fd, 8, SEEK_SET);
+ read(fd, buf, 8);
+ pos = 0;
+ for(i=0;i<8;i++)
+ pos |= buf[i] << (56 - i * 8);
+ return pos;
+}
+
+void ffm_write_write_index(int fd, offset_t pos)
+{
+ UINT8 buf[8];
+ int i;
+
+ for(i=0;i<8;i++)
+ buf[i] = (pos >> (56 - i * 8)) & 0xff;
+ lseek(fd, 8, SEEK_SET);
+ write(fd, buf, 8);
+}
+
+void ffm_set_write_index(AVFormatContext *s, offset_t pos, offset_t file_size)
+{
+ FFMContext *ffm = s->priv_data;
+ ffm->write_index = pos;
+ ffm->file_size = file_size;
+}
+
+static int ffm_read_close(AVFormatContext *s)
+{
+ AVStream *st;
+ int i;
+
+ for(i=0;i<s->nb_streams;i++) {
+ st = s->streams[i];
+ free(st->priv_data);
+ }
+ free(s->priv_data);
+ return 0;
+}
+
+AVFormat ffm_format = {
+ "ffm",
+ "ffm format",
+ "",
+ "ffm",
+ /* not really used */
+ CODEC_ID_MP2,
+ CODEC_ID_MPEG1VIDEO,
+ ffm_write_header,
+ ffm_write_packet,
+ ffm_write_trailer,
+ ffm_read_header,
+ ffm_read_packet,
+ ffm_read_close,
+ ffm_seek,
+};