/* Probabilistic content detection strategy: There is no file signature
* so perform sanity checks on various header parameters:
* 8000 <= sample rate (16 bits) <= 48000 ==> 40001 acceptable numbers
+ * flags <= 0x03 (2 LSBs are used) ==> 4 acceptable numbers
* compression type (8 bits) = 1 or 99 ==> 2 acceptable numbers
- * There is a total of 24 bits. The number space contains 2^24 =
- * 16777216 numbers. There are 40001 * 2 = 80002 acceptable combinations
- * of numbers. There is a 80002/16777216 = 0.48% chance of a false
- * positive.
+ * first audio chunk signature (32 bits) ==> 1 acceptable number
+ * The number space contains 2^64 numbers. There are 40001 * 4 * 2 * 1 =
+ * 320008 acceptable number combinations.
*/
- if (p->buf_size < AUD_HEADER_SIZE)
+ if (p->buf_size < AUD_HEADER_SIZE + AUD_CHUNK_PREAMBLE_SIZE)
return 0;
/* check sample rate */
if ((field < 8000) || (field > 48000))
return 0;
+ /* enforce the rule that the top 6 bits of this flags field are reserved (0);
+ * this might not be true, but enforce it until deemed unnecessary */
+ if (p->buf[10] & 0xFC)
+ return 0;
+
/* note: only check for WS IMA (type 99) right now since there is no
* support for type 1 */
if (p->buf[11] != 99)
return 0;
+ /* read ahead to the first audio chunk and validate the first header signature */
+ if (AV_RL32(&p->buf[16]) != AUD_CHUNK_SIGNATURE)
+ return 0;
+
/* return 1/2 certainty since this file check is a little sketchy */
return AVPROBE_SCORE_MAX / 2;
}
static int wsaud_read_header(AVFormatContext *s,
AVFormatParameters *ap)
{
- WsAudDemuxContext *wsaud = (WsAudDemuxContext *)s->priv_data;
- ByteIOContext *pb = &s->pb;
+ WsAudDemuxContext *wsaud = s->priv_data;
+ ByteIOContext *pb = s->pb;
AVStream *st;
unsigned char header[AUD_HEADER_SIZE];
if (get_buffer(pb, header, AUD_HEADER_SIZE) != AUD_HEADER_SIZE)
- return AVERROR_IO;
+ return AVERROR(EIO);
wsaud->audio_samplerate = AV_RL16(&header[0]);
if (header[11] == 99)
wsaud->audio_type = CODEC_ID_ADPCM_IMA_WS;
/* initialize the audio decoder stream */
st = av_new_stream(s, 0);
if (!st)
- return AVERROR_NOMEM;
+ return AVERROR(ENOMEM);
av_set_pts_info(st, 33, 1, wsaud->audio_samplerate);
st->codec->codec_type = CODEC_TYPE_AUDIO;
st->codec->codec_id = wsaud->audio_type;
static int wsaud_read_packet(AVFormatContext *s,
AVPacket *pkt)
{
- WsAudDemuxContext *wsaud = (WsAudDemuxContext *)s->priv_data;
- ByteIOContext *pb = &s->pb;
+ WsAudDemuxContext *wsaud = s->priv_data;
+ ByteIOContext *pb = s->pb;
unsigned char preamble[AUD_CHUNK_PREAMBLE_SIZE];
unsigned int chunk_size;
int ret = 0;
if (get_buffer(pb, preamble, AUD_CHUNK_PREAMBLE_SIZE) !=
AUD_CHUNK_PREAMBLE_SIZE)
- return AVERROR_IO;
+ return AVERROR(EIO);
/* validate the chunk */
if (AV_RL32(&preamble[4]) != AUD_CHUNK_SIGNATURE)
chunk_size = AV_RL16(&preamble[0]);
ret= av_get_packet(pb, pkt, chunk_size);
if (ret != chunk_size)
- return AVERROR_IO;
+ return AVERROR(EIO);
pkt->stream_index = wsaud->audio_stream_index;
pkt->pts = wsaud->audio_frame_counter;
pkt->pts /= wsaud->audio_samplerate;
static int wsaud_read_close(AVFormatContext *s)
{
-// WsAudDemuxContext *wsaud = (WsAudDemuxContext *)s->priv_data;
+// WsAudDemuxContext *wsaud = s->priv_data;
return 0;
}
static int wsvqa_read_header(AVFormatContext *s,
AVFormatParameters *ap)
{
- WsVqaDemuxContext *wsvqa = (WsVqaDemuxContext *)s->priv_data;
- ByteIOContext *pb = &s->pb;
+ WsVqaDemuxContext *wsvqa = s->priv_data;
+ ByteIOContext *pb = s->pb;
AVStream *st;
unsigned char *header;
unsigned char scratch[VQA_PREAMBLE_SIZE];
/* initialize the video decoder stream */
st = av_new_stream(s, 0);
if (!st)
- return AVERROR_NOMEM;
+ return AVERROR(ENOMEM);
av_set_pts_info(st, 33, 1, VQA_FRAMERATE);
wsvqa->video_stream_index = st->index;
st->codec->codec_type = CODEC_TYPE_VIDEO;
if (get_buffer(pb, st->codec->extradata, VQA_HEADER_SIZE) !=
VQA_HEADER_SIZE) {
av_free(st->codec->extradata);
- return AVERROR_IO;
+ return AVERROR(EIO);
}
st->codec->width = AV_RL16(&header[6]);
st->codec->height = AV_RL16(&header[8]);
if (AV_RL16(&header[24]) || (AV_RL16(&header[0]) == 1 && AV_RL16(&header[2]) == 1)) {
st = av_new_stream(s, 0);
if (!st)
- return AVERROR_NOMEM;
+ return AVERROR(ENOMEM);
av_set_pts_info(st, 33, 1, VQA_FRAMERATE);
st->codec->codec_type = CODEC_TYPE_AUDIO;
if (AV_RL16(&header[0]) == 1)
do {
if (get_buffer(pb, scratch, VQA_PREAMBLE_SIZE) != VQA_PREAMBLE_SIZE) {
av_free(st->codec->extradata);
- return AVERROR_IO;
+ return AVERROR(EIO);
}
chunk_tag = AV_RB32(&scratch[0]);
chunk_size = AV_RB32(&scratch[4]);
static int wsvqa_read_packet(AVFormatContext *s,
AVPacket *pkt)
{
- WsVqaDemuxContext *wsvqa = (WsVqaDemuxContext *)s->priv_data;
- ByteIOContext *pb = &s->pb;
+ WsVqaDemuxContext *wsvqa = s->priv_data;
+ ByteIOContext *pb = s->pb;
int ret = -1;
unsigned char preamble[VQA_PREAMBLE_SIZE];
unsigned int chunk_type;
if ((chunk_type == SND1_TAG) || (chunk_type == SND2_TAG) || (chunk_type == VQFR_TAG)) {
if (av_new_packet(pkt, chunk_size))
- return AVERROR_IO;
+ return AVERROR(EIO);
ret = get_buffer(pb, pkt->data, chunk_size);
if (ret != chunk_size) {
av_free_packet(pkt);
- return AVERROR_IO;
+ return AVERROR(EIO);
}
if (chunk_type == SND2_TAG) {
static int wsvqa_read_close(AVFormatContext *s)
{
-// WsVqaDemuxContext *wsvqa = (WsVqaDemuxContext *)s->priv_data;
+// WsVqaDemuxContext *wsvqa = s->priv_data;
return 0;
}