1
0
mirror of https://github.com/FFmpeg/FFmpeg.git synced 2024-11-21 10:55:51 +02:00

shorten: split reading of file header into a separate functions

This commit is contained in:
Justin Ruggles 2011-09-14 15:02:35 -04:00
parent 9ef6c7977f
commit a1f7885a8b

View File

@ -273,6 +273,73 @@ static void decode_subframe_lpc(ShortenContext *s, int channel, int residual_siz
}
}
static int read_header(ShortenContext *s)
{
int i;
int maxnlpc = 0;
/* shorten signature */
if (get_bits_long(&s->gb, 32) != AV_RB32("ajkg")) {
av_log(s->avctx, AV_LOG_ERROR, "missing shorten magic 'ajkg'\n");
return -1;
}
s->lpcqoffset = 0;
s->blocksize = DEFAULT_BLOCK_SIZE;
s->channels = 1;
s->nmean = -1;
s->version = get_bits(&s->gb, 8);
s->internal_ftype = get_uint(s, TYPESIZE);
s->channels = get_uint(s, CHANSIZE);
if (s->channels > MAX_CHANNELS) {
av_log(s->avctx, AV_LOG_ERROR, "too many channels: %d\n", s->channels);
return -1;
}
/* get blocksize if version > 0 */
if (s->version > 0) {
int skip_bytes;
s->blocksize = get_uint(s, av_log2(DEFAULT_BLOCK_SIZE));
maxnlpc = get_uint(s, LPCQSIZE);
s->nmean = get_uint(s, 0);
skip_bytes = get_uint(s, NSKIPSIZE);
for (i=0; i<skip_bytes; i++) {
skip_bits(&s->gb, 8);
}
}
s->nwrap = FFMAX(NWRAP, maxnlpc);
if (allocate_buffers(s))
return -1;
init_offset(s);
if (s->version > 1)
s->lpcqoffset = V2LPCQOFFSET;
if (get_ur_golomb_shorten(&s->gb, FNSIZE) != FN_VERBATIM) {
av_log(s->avctx, AV_LOG_ERROR, "missing verbatim section at beginning of stream\n");
return -1;
}
s->header_size = get_ur_golomb_shorten(&s->gb, VERBATIM_CKSIZE_SIZE);
if (s->header_size >= OUT_BUFFER_SIZE || s->header_size < CANONICAL_HEADER_SIZE) {
av_log(s->avctx, AV_LOG_ERROR, "header is wrong size: %d\n", s->header_size);
return -1;
}
for (i=0; i<s->header_size; i++)
s->header[i] = (char)get_ur_golomb_shorten(&s->gb, VERBATIM_BYTE_SIZE);
if (decode_wave_header(s->avctx, s->header, s->header_size) < 0)
return -1;
s->cur_chan = 0;
s->bitshift = 0;
return 0;
}
static int shorten_decode_frame(AVCodecContext *avctx,
void *data, int *data_size,
@ -311,67 +378,9 @@ static int shorten_decode_frame(AVCodecContext *avctx,
skip_bits(&s->gb, s->bitindex);
if (!s->blocksize)
{
int maxnlpc = 0;
/* shorten signature */
if (get_bits_long(&s->gb, 32) != AV_RB32("ajkg")) {
av_log(s->avctx, AV_LOG_ERROR, "missing shorten magic 'ajkg'\n");
return -1;
}
s->lpcqoffset = 0;
s->blocksize = DEFAULT_BLOCK_SIZE;
s->channels = 1;
s->nmean = -1;
s->version = get_bits(&s->gb, 8);
s->internal_ftype = get_uint(s, TYPESIZE);
s->channels = get_uint(s, CHANSIZE);
if (s->channels > MAX_CHANNELS) {
av_log(s->avctx, AV_LOG_ERROR, "too many channels: %d\n", s->channels);
return -1;
}
/* get blocksize if version > 0 */
if (s->version > 0) {
int skip_bytes;
s->blocksize = get_uint(s, av_log2(DEFAULT_BLOCK_SIZE));
maxnlpc = get_uint(s, LPCQSIZE);
s->nmean = get_uint(s, 0);
skip_bytes = get_uint(s, NSKIPSIZE);
for (i=0; i<skip_bytes; i++) {
skip_bits(&s->gb, 8);
}
}
s->nwrap = FFMAX(NWRAP, maxnlpc);
if (allocate_buffers(s))
return -1;
init_offset(s);
if (s->version > 1)
s->lpcqoffset = V2LPCQOFFSET;
if (get_ur_golomb_shorten(&s->gb, FNSIZE) != FN_VERBATIM) {
av_log(s->avctx, AV_LOG_ERROR, "missing verbatim section at beginning of stream\n");
return -1;
}
s->header_size = get_ur_golomb_shorten(&s->gb, VERBATIM_CKSIZE_SIZE);
if (s->header_size >= OUT_BUFFER_SIZE || s->header_size < CANONICAL_HEADER_SIZE) {
av_log(s->avctx, AV_LOG_ERROR, "header is wrong size: %d\n", s->header_size);
return -1;
}
for (i=0; i<s->header_size; i++)
s->header[i] = (char)get_ur_golomb_shorten(&s->gb, VERBATIM_BYTE_SIZE);
if (decode_wave_header(avctx, s->header, s->header_size) < 0)
return -1;
s->cur_chan = 0;
s->bitshift = 0;
int ret;
if ((ret = read_header(s)) < 0)
return ret;
}
else
{