static int dhav_read_header(AVFormatContext *s)
{
DHAVContext *dhav = s->priv_data;
uint8_t signature[5];
ffio_ensure_seekback(s->pb, 5);
avio_read(s->pb, signature, sizeof(signature));
if (!memcmp(signature, "DAHUA", 5))
avio_skip(s->pb, 0x400 - 5);
else
avio_seek(s->pb, -5, SEEK_CUR);
s->ctx_flags |= AVFMTCTX_NOHEADER;
dhav->video_stream_index = -1;
dhav->audio_stream_index = -1;
return 0;
}
static int mpjpeg_read_packet(AVFormatContext *s, AVPacket *pkt)
{
int size;
int ret;
MPJPEGDemuxContext *mpjpeg = s->priv_data;
if (mpjpeg->boundary == NULL) {
uint8_t* boundary = NULL;
if (mpjpeg->strict_mime_boundary) {
boundary = mpjpeg_get_boundary(s->pb);
}
if (boundary != NULL) {
mpjpeg->boundary = boundary;
mpjpeg->searchstr = av_asprintf( "\r\n%s\r\n", boundary );
} else {
mpjpeg->boundary = av_strdup("--");
mpjpeg->searchstr = av_strdup("\r\n--");
}
if (!mpjpeg->boundary || !mpjpeg->searchstr) {
av_freep(&mpjpeg->boundary);
av_freep(&mpjpeg->searchstr);
return AVERROR(ENOMEM);
}
mpjpeg->searchstr_len = strlen(mpjpeg->searchstr);
}
ret = parse_multipart_header(s->pb, &size, mpjpeg->boundary, s);
if (ret < 0)
return ret;
if (size > 0) {
/* size has been provided to us in MIME header */
ret = av_get_packet(s->pb, pkt, size);
} else {
/* no size was given -- we read until the next boundary or end-of-file */
int remaining = 0, len;
const int read_chunk = 2048;
av_init_packet(pkt);
pkt->data = NULL;
pkt->size = 0;
pkt->pos = avio_tell(s->pb);
/* we may need to return as much as all we've read back to the buffer */
ffio_ensure_seekback(s->pb, read_chunk);
while ((ret = av_append_packet(s->pb, pkt, read_chunk - remaining)) >= 0) {
/* scan the new data */
char *start;
len = ret + remaining;
start = pkt->data + pkt->size - len;
do {
if (!memcmp(start, mpjpeg->searchstr, mpjpeg->searchstr_len)) {
// got the boundary! rewind the stream
avio_seek(s->pb, -(len-2), SEEK_CUR);
pkt->size -= (len-2);
return pkt->size;
}
len--;
start++;
} while (len >= mpjpeg->searchstr_len);
remaining = len;
}
/* error or EOF occurred */
if (ret == AVERROR_EOF) {
ret = pkt->size > 0 ? pkt->size : AVERROR_EOF;
} else {
av_packet_unref(pkt);
}
}
return ret;
}
static int apng_read_packet(AVFormatContext *s, AVPacket *pkt)
{
APNGDemuxContext *ctx = s->priv_data;
int ret;
int64_t size;
AVIOContext *pb = s->pb;
uint32_t len, tag;
/*
* fcTL chunk length, in bytes:
* 4 (length)
* 4 (tag)
* 26 (actual chunk)
* 4 (crc) bytes
* and needed next:
* 4 (length)
* 4 (tag (must be fdAT or IDAT))
*/
/* if num_play is not 1, then the seekback is already guaranteed */
if (ctx->num_play == 1 && (ret = ffio_ensure_seekback(pb, 46)) < 0)
return ret;
len = avio_rb32(pb);
tag = avio_rl32(pb);
switch (tag) {
case MKTAG('f', 'c', 'T', 'L'):
if (len != 26)
return AVERROR_INVALIDDATA;
if ((ret = decode_fctl_chunk(s, ctx, pkt)) < 0)
return ret;
/* fcTL must precede fdAT or IDAT */
len = avio_rb32(pb);
tag = avio_rl32(pb);
if (len > 0x7fffffff ||
tag != MKTAG('f', 'd', 'A', 'T') &&
tag != MKTAG('I', 'D', 'A', 'T'))
return AVERROR_INVALIDDATA;
size = 38 /* fcTL */ + 8 /* len, tag */ + len + 4 /* crc */;
if (size > INT_MAX)
return AVERROR(EINVAL);
if ((ret = avio_seek(pb, -46, SEEK_CUR)) < 0 ||
(ret = av_append_packet(pb, pkt, size)) < 0)
return ret;
if (ctx->num_play == 1 && (ret = ffio_ensure_seekback(pb, 8)) < 0)
return ret;
len = avio_rb32(pb);
tag = avio_rl32(pb);
while (tag &&
tag != MKTAG('f', 'c', 'T', 'L') &&
tag != MKTAG('I', 'E', 'N', 'D')) {
if (len > 0x7fffffff)
return AVERROR_INVALIDDATA;
if ((ret = avio_seek(pb, -8, SEEK_CUR)) < 0 ||
(ret = av_append_packet(pb, pkt, len + 12)) < 0)
return ret;
if (ctx->num_play == 1 && (ret = ffio_ensure_seekback(pb, 8)) < 0)
return ret;
len = avio_rb32(pb);
tag = avio_rl32(pb);
}
if ((ret = avio_seek(pb, -8, SEEK_CUR)) < 0)
return ret;
if (ctx->is_key_frame)
pkt->flags |= AV_PKT_FLAG_KEY;
return ret;
case MKTAG('I', 'E', 'N', 'D'):
ctx->cur_loop++;
if (ctx->ignore_loop || ctx->num_play >= 1 && ctx->cur_loop == ctx->num_play) {
avio_seek(pb, -8, SEEK_CUR);
return AVERROR_EOF;
}
if ((ret = avio_seek(pb, s->streams[0]->codec->extradata_size + 8, SEEK_SET)) < 0)
return ret;
return 0;
default:
{
char tag_buf[5];
av_get_codec_tag_string(tag_buf, sizeof(tag_buf), tag);
avpriv_request_sample(s, "In-stream tag=%s (0x%08X) len=%"PRIu32, tag_buf, tag, len);
avio_skip(pb, len + 4);
}
}
/* Handle the unsupported yet cases */
return AVERROR_PATCHWELCOME;
}
static int apng_read_header(AVFormatContext *s)
{
APNGDemuxContext *ctx = s->priv_data;
AVIOContext *pb = s->pb;
uint32_t len, tag;
AVStream *st;
int ret = AVERROR_INVALIDDATA, acTL_found = 0;
/* verify PNGSIG */
if (avio_rb64(pb) != PNGSIG)
return ret;
/* parse IHDR (must be first chunk) */
len = avio_rb32(pb);
tag = avio_rl32(pb);
if (len != 13 || tag != MKTAG('I', 'H', 'D', 'R'))
return ret;
st = avformat_new_stream(s, NULL);
if (!st)
return AVERROR(ENOMEM);
st->codec->codec_type = AVMEDIA_TYPE_VIDEO;
st->codec->codec_id = AV_CODEC_ID_APNG;
st->codec->width = avio_rb32(pb);
st->codec->height = avio_rb32(pb);
if ((ret = av_image_check_size(st->codec->width, st->codec->height, 0, s)) < 0)
return ret;
/* extradata will contain every chunk up to the first fcTL (excluded) */
st->codec->extradata = av_malloc(len + 12 + FF_INPUT_BUFFER_PADDING_SIZE);
if (!st->codec->extradata)
return AVERROR(ENOMEM);
st->codec->extradata_size = len + 12;
AV_WB32(st->codec->extradata, len);
AV_WL32(st->codec->extradata+4, tag);
AV_WB32(st->codec->extradata+8, st->codec->width);
AV_WB32(st->codec->extradata+12, st->codec->height);
if ((ret = avio_read(pb, st->codec->extradata+16, 9)) < 0)
goto fail;
while (!avio_feof(pb)) {
if (acTL_found && ctx->num_play != 1) {
int64_t size = avio_size(pb);
int64_t offset = avio_tell(pb);
if (size < 0) {
ret = size;
goto fail;
} else if (offset < 0) {
ret = offset;
goto fail;
} else if ((ret = ffio_ensure_seekback(pb, size - offset)) < 0) {
av_log(s, AV_LOG_WARNING, "Could not ensure seekback, will not loop\n");
ctx->num_play = 1;
}
}
if ((ctx->num_play == 1 || !acTL_found) &&
((ret = ffio_ensure_seekback(pb, 4 /* len */ + 4 /* tag */)) < 0))
goto fail;
len = avio_rb32(pb);
if (len > 0x7fffffff) {
ret = AVERROR_INVALIDDATA;
goto fail;
}
tag = avio_rl32(pb);
switch (tag) {
case MKTAG('a', 'c', 'T', 'L'):
if ((ret = avio_seek(pb, -8, SEEK_CUR)) < 0 ||
(ret = append_extradata(st->codec, pb, len + 12)) < 0)
goto fail;
acTL_found = 1;
ctx->num_frames = AV_RB32(st->codec->extradata + ret + 8);
ctx->num_play = AV_RB32(st->codec->extradata + ret + 12);
av_log(s, AV_LOG_DEBUG, "num_frames: %"PRIu32", num_play: %"PRIu32"\n",
ctx->num_frames, ctx->num_play);
break;
case MKTAG('f', 'c', 'T', 'L'):
if (!acTL_found) {
ret = AVERROR_INVALIDDATA;
goto fail;
}
if ((ret = avio_seek(pb, -8, SEEK_CUR)) < 0)
goto fail;
return 0;
default:
if ((ret = avio_seek(pb, -8, SEEK_CUR)) < 0 ||
(ret = append_extradata(st->codec, pb, len + 12)) < 0)
goto fail;
}
}
fail:
if (st->codec->extradata_size) {
av_freep(&st->codec->extradata);
st->codec->extradata_size = 0;
}
return ret;
}