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author | Justin Ruggles <justin.ruggles@gmail.com> | 2011-09-07 15:28:07 -0400 |
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committer | Justin Ruggles <justin.ruggles@gmail.com> | 2011-09-22 14:11:34 -0400 |
commit | 1993c6849cf93f90066e4490c1547e2db845050c (patch) | |
tree | 6c757f1d06676daaf7bf59085a22aa256eeb41cd /libavcodec | |
parent | fda459cee7a4227c34dfbc5dca1427c00d0d792e (diff) | |
download | ffmpeg-streaming-1993c6849cf93f90066e4490c1547e2db845050c.zip ffmpeg-streaming-1993c6849cf93f90066e4490c1547e2db845050c.tar.gz |
8svx/iff: fix decoding of compressed stereo 8svx files.
Make the iff demuxer send the whole audio chunk to the decoder as a
single packet and move stereo interleaving from the iff demuxer to the
decoder.
Based on a patch by Stefano Sabatini.
git.videolan.org/ffmpeg.git
commit e280a4da2ae6fd44f0079358ecc5aa08e388a5ed
Diffstat (limited to 'libavcodec')
-rw-r--r-- | libavcodec/8svx.c | 101 |
1 files changed, 83 insertions, 18 deletions
diff --git a/libavcodec/8svx.c b/libavcodec/8svx.c index af3b5fe..a7b9c86 100644 --- a/libavcodec/8svx.c +++ b/libavcodec/8svx.c @@ -32,8 +32,14 @@ /** decoder context */ typedef struct EightSvxContext { - uint8_t fib_acc; + uint8_t fib_acc[2]; const int8_t *table; + + /* buffer used to store the whole first packet. + data is only sent as one large packet */ + uint8_t *data[2]; + int data_size; + int data_idx; } EightSvxContext; static const int8_t fibonacci[16] = { -34, -21, -13, -8, -5, -3, -2, -1, @@ -41,6 +47,8 @@ static const int8_t fibonacci[16] = { -34, -21, -13, -8, -5, -3, -2, -1, static const int8_t exponential[16] = { -128, -64, -32, -16, -8, -4, -2, -1, 0, 1, 2, 4, 8, 16, 32, 64 }; +#define MAX_FRAME_SIZE 32768 + /** * Delta decode the compressed values in src, and put the resulting * decoded samples in dst. @@ -48,16 +56,18 @@ static const int8_t exponential[16] = { -128, -64, -32, -16, -8, -4, -2, -1, * @param[in,out] state starting value. it is saved for use in the next call. */ static void delta_decode(uint8_t *dst, const uint8_t *src, int src_size, - uint8_t *state, const int8_t *table) + uint8_t *state, const int8_t *table, int channels) { uint8_t val = *state; while (src_size--) { uint8_t d = *src++; val = av_clip_uint8(val + table[d & 0xF]); - *dst++ = val; + *dst = val; + dst += channels; val = av_clip_uint8(val + table[d >> 4]); - *dst++ = val; + *dst = val; + dst += channels; } *state = val; @@ -67,33 +77,69 @@ static void delta_decode(uint8_t *dst, const uint8_t *src, int src_size, static int eightsvx_decode_frame(AVCodecContext *avctx, void *data, int *data_size, AVPacket *avpkt) { - const uint8_t *buf = avpkt->data; - int buf_size = avpkt->size; EightSvxContext *esc = avctx->priv_data; + int buf_size; uint8_t *out_data = data; - int consumed = buf_size; + int out_data_size; + + /* for the first packet, copy data to buffer */ + if (avpkt->data) { + int chan_size = (avpkt->size / avctx->channels) - 2; - if(avctx->frame_number == 0) { - if (buf_size < 2) { + if (avpkt->size < 2) { av_log(avctx, AV_LOG_ERROR, "packet size is too small\n"); return AVERROR(EINVAL); } - esc->fib_acc = (int8_t)buf[1] + 128; - buf_size -= 2; - buf += 2; + if (esc->data[0]) { + av_log(avctx, AV_LOG_ERROR, "unexpected data after first packet\n"); + return AVERROR(EINVAL); + } + + esc->fib_acc[0] = avpkt->data[1] + 128; + if (avctx->channels == 2) + esc->fib_acc[1] = avpkt->data[2+chan_size+1] + 128; + + esc->data_idx = 0; + esc->data_size = chan_size; + if (!(esc->data[0] = av_malloc(chan_size))) + return AVERROR(ENOMEM); + if (avctx->channels == 2) { + if (!(esc->data[1] = av_malloc(chan_size))) { + av_freep(&esc->data[0]); + return AVERROR(ENOMEM); + } + } + memcpy(esc->data[0], &avpkt->data[2], chan_size); + if (avctx->channels == 2) + memcpy(esc->data[1], &avpkt->data[2+chan_size+2], chan_size); + } + if (!esc->data[0]) { + av_log(avctx, AV_LOG_ERROR, "unexpected empty packet\n"); + return AVERROR(EINVAL); } - if (*data_size < buf_size * 2) { + /* decode next piece of data from the buffer */ + buf_size = FFMIN(MAX_FRAME_SIZE, esc->data_size - esc->data_idx); + if (buf_size <= 0) { + *data_size = 0; + return avpkt->size; + } + out_data_size = buf_size * 2 * avctx->channels; + if (*data_size < out_data_size) { av_log(avctx, AV_LOG_ERROR, "Provided buffer with size %d is too small.\n", *data_size); return AVERROR(EINVAL); } + delta_decode(out_data, &esc->data[0][esc->data_idx], buf_size, + &esc->fib_acc[0], esc->table, avctx->channels); + if (avctx->channels == 2) { + delta_decode(&out_data[1], &esc->data[1][esc->data_idx], buf_size, + &esc->fib_acc[1], esc->table, avctx->channels); + } + esc->data_idx += buf_size; + *data_size = out_data_size; - delta_decode(out_data, buf, buf_size, &esc->fib_acc, esc->table); - - *data_size = buf_size * 2; - - return consumed; + return avpkt->size; } /** initialize 8svx decoder */ @@ -101,6 +147,11 @@ static av_cold int eightsvx_decode_init(AVCodecContext *avctx) { EightSvxContext *esc = avctx->priv_data; + if (avctx->channels < 1 || avctx->channels > 2) { + av_log(avctx, AV_LOG_ERROR, "8SVX does not support more than 2 channels\n"); + return AVERROR(EINVAL); + } + switch(avctx->codec->id) { case CODEC_ID_8SVX_FIB: esc->table = fibonacci; @@ -115,13 +166,25 @@ static av_cold int eightsvx_decode_init(AVCodecContext *avctx) return 0; } +static av_cold int eightsvx_decode_close(AVCodecContext *avctx) +{ + EightSvxContext *esc = avctx->priv_data; + + av_freep(&esc->data[0]); + av_freep(&esc->data[1]); + + return 0; +} + AVCodec ff_eightsvx_fib_decoder = { .name = "8svx_fib", .type = AVMEDIA_TYPE_AUDIO, .id = CODEC_ID_8SVX_FIB, .priv_data_size = sizeof (EightSvxContext), .init = eightsvx_decode_init, + .close = eightsvx_decode_close, .decode = eightsvx_decode_frame, + .capabilities = CODEC_CAP_DELAY, .long_name = NULL_IF_CONFIG_SMALL("8SVX fibonacci"), }; @@ -131,6 +194,8 @@ AVCodec ff_eightsvx_exp_decoder = { .id = CODEC_ID_8SVX_EXP, .priv_data_size = sizeof (EightSvxContext), .init = eightsvx_decode_init, + .close = eightsvx_decode_close, .decode = eightsvx_decode_frame, + .capabilities = CODEC_CAP_DELAY, .long_name = NULL_IF_CONFIG_SMALL("8SVX exponential"), }; |