shorten decoder by (Jeff Muizelaar <jrmuizel gmail com>)

Originally committed as revision 3984 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/allcodecs.c

@@ -194,6 +194,7 @@ void avcodec_register_all(void)
     register_avcodec(&sol_dpcm_decoder);
     register_avcodec(&qtrle_decoder);
     register_avcodec(&flac_decoder);
+    register_avcodec(&shorten_decoder);
 #endif /* CONFIG_DECODERS */
 
 #ifdef AMR_NB

libavcodec/avcodec.h

@@ -164,6 +164,7 @@ enum CodecID {
     CODEC_ID_FLAC,
     CODEC_ID_MP3ADU,
     CODEC_ID_MP3ON4,
+    CODEC_ID_SHORTEN,
     
     CODEC_ID_OGGTHEORA= 0x16000, 
     
@@ -2008,6 +2009,7 @@ extern AVCodec ulti_decoder;
 extern AVCodec qdraw_decoder;
 extern AVCodec xl_decoder;
 extern AVCodec qpeg_decoder;
+extern AVCodec shorten_decoder;
 
 /* pcm codecs */
 #define PCM_CODEC(id, name) \

libavcodec/golomb.h

@@ -284,6 +284,27 @@ static inline int get_sr_golomb_flac(GetBitContext *gb, int k, int limit, int es
     return (v>>1) ^ -(v&1);
 }
 
+/**
+ * read unsigned golomb rice code (shorten).
+ */
+static inline unsigned int get_ur_golomb_shorten(GetBitContext *gb, int k){
+	return get_ur_golomb_jpegls(gb, k, INT_MAX, 0);
+}
+
+/**
+ * read signed golomb rice code (shorten).
+ */
+static inline int get_sr_golomb_shorten(GetBitContext* gb, int k)
+{
+    int uvar = get_ur_golomb_jpegls(gb, k + 1, INT_MAX, 0);
+    if (uvar & 1)
+        return ~(uvar >> 1);
+    else
+        return uvar >> 1;
+}
+
+
+
 #ifdef TRACE
 
 static inline int get_ue(GetBitContext *s, char *file, const char *func, int line){

libavcodec/shorten.c

@@ -0,0 +1,521 @@
+/*
+ * Shorten decoder
+ * Copyright (c) 2005 Jeff Muizelaar
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ */
+
+/**
+ * @file shorten.c
+ * Shorten decoder
+ * @author Jeff Muizelaar
+ *
+ */
+
+#define DEBUG
+#include <limits.h>
+#include "avcodec.h"
+#include "bitstream.h"
+#include "golomb.h"
+
+#define MAX_CHANNELS 8
+#define MAX_BLOCKSIZE 65535
+
+#define OUT_BUFFER_SIZE 16384
+
+#define ULONGSIZE 2
+
+#define WAVE_FORMAT_PCM 0x0001
+
+#define DEFAULT_BLOCK_SIZE 256
+
+#define TYPESIZE 4
+#define CHANSIZE 0
+#define LPCQSIZE 2
+#define ENERGYSIZE 3
+#define BITSHIFTSIZE 2
+
+#define TYPE_S16HL 3
+#define TYPE_S16LH 5
+
+#define NWRAP 3
+#define NSKIPSIZE 1
+
+#define LPCQUANT 5
+#define V2LPCQOFFSET (1 << LPCQUANT)
+
+#define FNSIZE 2
+#define FN_DIFF0        0
+#define FN_DIFF1        1
+#define FN_DIFF2        2
+#define FN_DIFF3        3
+#define FN_QUIT         4
+#define FN_BLOCKSIZE    5
+#define FN_BITSHIFT     6
+#define FN_QLPC         7
+#define FN_ZERO         8
+#define FN_VERBATIM     9
+
+#define VERBATIM_CKSIZE_SIZE 5
+#define VERBATIM_BYTE_SIZE 8
+#define CANONICAL_HEADER_SIZE 44
+
+typedef struct ShortenContext {
+    AVCodecContext *avctx;
+    GetBitContext gb;
+
+    int min_framesize, max_framesize;
+    int channels;
+
+    int32_t *decoded[MAX_CHANNELS];
+    int32_t *offset[MAX_CHANNELS];
+    uint8_t *bitstream;
+    int bitstream_size;
+    int bitstream_index;
+    int allocated_bitstream_size;
+    int header_size;
+    uint8_t header[OUT_BUFFER_SIZE];
+    int version;
+    int cur_chan;
+    int bitshift;
+    int nmean;
+    int internal_ftype;
+    int nwrap;
+    int blocksize;
+    int bitindex;
+    int32_t lpcqoffset;
+} ShortenContext;
+
+static int shorten_decode_init(AVCodecContext * avctx)
+{
+    ShortenContext *s = avctx->priv_data;
+    s->avctx = avctx;
+
+    return 0;
+}
+
+static void allocate_buffers(ShortenContext *s)
+{
+    int i, chan;
+    for (chan=0; chan<s->channels; chan++) {
+        s->offset[chan] = av_realloc(s->offset[chan], sizeof(int32_t)*FFMAX(1, s->nmean));
+
+        s->decoded[chan] = av_realloc(s->decoded[chan], sizeof(int32_t)*(s->blocksize + s->nwrap));
+        for (i=0; i<s->nwrap; i++)
+            s->decoded[chan][i] = 0;
+        s->decoded[chan] += s->nwrap;
+
+    }
+}
+
+
+static inline unsigned int get_uint(ShortenContext *s, int k)
+{
+    if (s->version != 0)
+        k = get_ur_golomb_shorten(&s->gb, ULONGSIZE);
+    return get_ur_golomb_shorten(&s->gb, k);
+}
+
+
+static void fix_bitshift(ShortenContext *s, int32_t *buffer)
+{
+    int i;
+
+    if (s->bitshift != 0)
+        for (i = 0; i < s->blocksize; i++)
+            buffer[s->nwrap + i] <<= s->bitshift;
+}
+
+
+static void init_offset(ShortenContext *s)
+{
+    int32_t mean = 0;
+    int  chan, i;
+    int nblock = FFMAX(1, s->nmean);
+    /* initialise offset */
+    switch (s->internal_ftype)
+    {
+        case TYPE_S16HL:
+        case TYPE_S16LH:
+            mean = 0;
+            break;
+        default:
+            av_log(s->avctx, AV_LOG_ERROR, "unknown audio type");
+            abort();
+    }
+
+    for (chan = 0; chan < s->channels; chan++)
+        for (i = 0; i < nblock; i++)
+            s->offset[chan][i] = mean;
+}
+
+static int inline get_le32(GetBitContext *gb)
+{
+    return bswap_32(get_bits_long(gb, 32));
+}
+
+static short inline get_le16(GetBitContext *gb)
+{
+    return bswap_16(get_bits_long(gb, 16));
+}
+
+static int decode_wave_header(AVCodecContext *avctx, uint8_t *header, int header_size)
+{
+    GetBitContext hb;
+    int len;
+    int chunk_size;
+    short wave_format;
+
+    init_get_bits(&hb, header, header_size*8);
+    if (get_le32(&hb) != MKTAG('R','I','F','F')) {
+        av_log(avctx, AV_LOG_ERROR, "missing RIFF tag\n");
+        return -1;
+    }
+
+    chunk_size = get_le32(&hb);
+
+    if (get_le32(&hb) != MKTAG('W','A','V','E')) {
+        av_log(avctx, AV_LOG_ERROR, "missing WAVE tag\n");
+        return -1;
+    }
+
+    while (get_le32(&hb) != MKTAG('f','m','t',' ')) {
+        len = get_le32(&hb);
+        skip_bits(&hb, 8*len);
+    }
+    len = get_le32(&hb);
+
+    if (len < 16) {
+        av_log(avctx, AV_LOG_ERROR, "fmt chunk was too short\n");
+        return -1;
+    }
+
+    wave_format = get_le16(&hb);
+
+    switch (wave_format) {
+        case WAVE_FORMAT_PCM:
+            break;
+        default:
+            av_log(avctx, AV_LOG_ERROR, "unsupported wave format\n");
+            return -1;
+    }
+
+    avctx->channels = get_le16(&hb);
+    avctx->sample_rate = get_le32(&hb);
+    avctx->bit_rate = get_le32(&hb) * 8;
+    avctx->block_align = get_le16(&hb);
+    avctx->bits_per_sample = get_le16(&hb);
+
+    if (avctx->bits_per_sample != 16) {
+        av_log(avctx, AV_LOG_ERROR, "unsupported number of bits per sample\n");
+        return -1;
+    }
+
+    len -= 16;
+    if (len > 0)
+        av_log(avctx, AV_LOG_INFO, "%d header bytes unparsed\n", len);
+
+    return 0;
+}
+
+static int16_t * interleave_buffer(int16_t *samples, int nchan, int blocksize, int32_t **buffer) {
+    int i, chan;
+    for (i=0; i<blocksize; i++)
+        for (chan=0; chan < nchan; chan++)
+            *samples++ = FFMIN(buffer[chan][i], 32768);
+    return samples;
+}
+
+static void decode_subframe_lpc(ShortenContext *s, int channel, int residual_size, int pred_order)
+{
+    int sum, i, j;
+    int coeffs[pred_order];
+
+    for (i=0; i<pred_order; i++)
+        coeffs[i] = get_sr_golomb_shorten(&s->gb, LPCQUANT);
+
+    for (i=0; i < s->blocksize; i++) {
+        sum = s->lpcqoffset;
+        for (j=0; j<pred_order; j++)
+            sum += coeffs[j] * s->decoded[channel][i-j-1];
+        s->decoded[channel][i] = get_sr_golomb_shorten(&s->gb, residual_size) + (sum >> LPCQUANT);
+    }
+}
+
+
+static int shorten_decode_frame(AVCodecContext *avctx,
+        void *data, int *data_size,
+        uint8_t *buf, int buf_size)
+{
+    ShortenContext *s = avctx->priv_data;
+    int i, input_buf_size = 0;
+    int16_t *samples = data;
+    if(s->max_framesize == 0){
+        s->max_framesize= 1024; // should hopefully be enough for the first header
+        s->bitstream= av_fast_realloc(s->bitstream, &s->allocated_bitstream_size, s->max_framesize);
+    }
+
+    if(1 && s->max_framesize){//FIXME truncated
+        buf_size= FFMIN(buf_size, s->max_framesize - s->bitstream_size);
+        input_buf_size= buf_size;
+
+        if(s->bitstream_index + s->bitstream_size + buf_size > s->allocated_bitstream_size){
+            //                printf("memmove\n");
+            memmove(s->bitstream, &s->bitstream[s->bitstream_index], s->bitstream_size);
+            s->bitstream_index=0;
+        }
+        memcpy(&s->bitstream[s->bitstream_index + s->bitstream_size], buf, buf_size);
+        buf= &s->bitstream[s->bitstream_index];
+        buf_size += s->bitstream_size;
+        s->bitstream_size= buf_size;
+
+        if(buf_size < s->max_framesize){
+            //dprintf("wanna more data ... %d\n", buf_size);
+            return input_buf_size;
+        }
+    }
+    init_get_bits(&s->gb, buf, buf_size*8);
+    get_bits(&s->gb, s->bitindex);
+    if (!s->blocksize)
+    {
+        int maxnlpc = 0;
+        /* shorten signature */
+        if (get_bits_long(&s->gb, 32) != bswap_32(ff_get_fourcc("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);
+
+        allocate_buffers(s);
+
+        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 begining 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;
+    }
+    else
+    {
+        int cmd;
+        int len;
+        cmd = get_ur_golomb_shorten(&s->gb, FNSIZE);
+        switch (cmd) {
+            case FN_ZERO:
+            case FN_DIFF0:
+            case FN_DIFF1:
+            case FN_DIFF2:
+            case FN_DIFF3:
+            case FN_QLPC:
+                {
+                    int residual_size = 0;
+                    int channel = s->cur_chan;
+                    int32_t coffset;
+                    if (cmd != FN_ZERO) {
+                        residual_size = get_ur_golomb_shorten(&s->gb, ENERGYSIZE);
+                        /* this is a hack as version 0 differed in defintion of get_sr_golomb_shorten */
+                        if (s->version == 0)
+                            residual_size--;
+                    }
+
+                    if (s->nmean == 0)
+                        coffset = s->offset[channel][0];
+                    else {
+                        int32_t sum = (s->version < 2) ? 0 : s->nmean / 2;
+                        for (i=0; i<s->nmean; i++)
+                            sum += s->offset[channel][i];
+                        coffset = sum / s->nmean;
+                        if (s->version >= 2)
+                            coffset >>= FFMIN(1, s->bitshift);
+                    }
+                    switch (cmd) {
+                        case FN_ZERO:
+                            for (i=0; i<s->blocksize; i++)
+                                s->decoded[channel][i] = 0;
+                            break;
+                        case FN_DIFF0:
+                            for (i=0; i<s->blocksize; i++)
+                                s->decoded[channel][i] = get_sr_golomb_shorten(&s->gb, residual_size) + coffset;
+                            break;
+                        case FN_DIFF1:
+                            for (i=0; i<s->blocksize; i++)
+                                s->decoded[channel][i] = get_sr_golomb_shorten(&s->gb, residual_size) + s->decoded[channel][i - 1];
+                            break;
+                        case FN_DIFF2:
+                            for (i=0; i<s->blocksize; i++)
+                                s->decoded[channel][i] = get_sr_golomb_shorten(&s->gb, residual_size) + 2*s->decoded[channel][i-1]
+                                                                                                      -   s->decoded[channel][i-2];
+                            break;
+                        case FN_DIFF3:
+                            for (i=0; i<s->blocksize; i++)
+                                s->decoded[channel][i] = get_sr_golomb_shorten(&s->gb, residual_size) + 3*s->decoded[channel][i-1]
+                                                                                                      - 3*s->decoded[channel][i-2]
+                                                                                                      +   s->decoded[channel][i-3];
+                            break;
+                        case FN_QLPC:
+                            {
+                                int pred_order = get_ur_golomb_shorten(&s->gb, LPCQSIZE);
+                                for (i=0; i<pred_order; i++)
+                                    s->decoded[channel][i - pred_order] -= coffset;
+                                decode_subframe_lpc(s, channel, residual_size, pred_order);
+                                if (coffset != 0)
+                                    for (i=0; i < s->blocksize; i++)
+                                        s->decoded[channel][i] += coffset;
+                            }
+                    }
+                    if (s->nmean > 0) {
+                        int32_t sum = (s->version < 2) ? 0 : s->blocksize / 2;
+                        for (i=0; i<s->blocksize; i++)
+                            sum += s->decoded[channel][i];
+
+                        for (i=1; i<s->nmean; i++)
+                            s->offset[channel][i-1] = s->offset[channel][i];
+
+                        if (s->version < 2)
+                            s->offset[channel][s->nmean - 1] = sum / s->blocksize;
+                        else
+                            s->offset[channel][s->nmean - 1] = (sum / s->blocksize) << s->bitshift;
+                    }
+                    for (i=-s->nwrap; i<0; i++)
+                        s->decoded[channel][i] = s->decoded[channel][i + s->blocksize];
+
+                    fix_bitshift(s, s->decoded[channel]);
+
+                    s->cur_chan++;
+                    if (s->cur_chan == s->channels) {
+                        samples = interleave_buffer(samples, s->channels, s->blocksize, s->decoded);
+                        s->cur_chan = 0;
+                        goto frame_done;
+                    }
+                    break;
+                }
+                break;
+            case FN_VERBATIM:
+                len = get_ur_golomb_shorten(&s->gb, VERBATIM_CKSIZE_SIZE);
+                while (len--) {
+                    get_ur_golomb_shorten(&s->gb, VERBATIM_BYTE_SIZE);
+                }
+                break;
+            case FN_BITSHIFT:
+                s->bitshift = get_ur_golomb_shorten(&s->gb, BITSHIFTSIZE);
+                break;
+            case FN_BLOCKSIZE:
+                s->blocksize = get_uint(s, av_log2(s->blocksize));
+                break;
+            case FN_QUIT:
+                return buf_size;
+                break;
+            default:
+                av_log(avctx, AV_LOG_ERROR, "unknown shorten function %d\n", cmd);
+                return -1;
+                break;
+        }
+    }
+frame_done:
+    *data_size = (int8_t *)samples - (int8_t *)data;
+
+    //    s->last_blocksize = s->blocksize;
+    s->bitindex = get_bits_count(&s->gb) - 8*((get_bits_count(&s->gb))/8);
+    i= (get_bits_count(&s->gb))/8;
+    if (i > buf_size) {
+        av_log(s->avctx, AV_LOG_ERROR, "overread: %d\n", i - buf_size);
+        s->bitstream_size=0;
+        s->bitstream_index=0;
+        return -1;
+    }
+    if (s->bitstream_size) {
+        s->bitstream_index += i;
+        s->bitstream_size  -= i;
+        return input_buf_size;
+    } else
+        return i;
+}
+
+static int shorten_decode_close(AVCodecContext *avctx)
+{
+    ShortenContext *s = avctx->priv_data;
+    int i;
+
+    for (i = 0; i < s->channels; i++) {
+        s->decoded[i] -= s->nwrap;
+        av_freep(&s->decoded[i]);
+        av_freep(&s->offset[i]);
+    }
+    av_freep(&s->bitstream);
+    return 0;
+}
+
+static void shorten_flush(AVCodecContext *avctx){
+    ShortenContext *s = avctx->priv_data;
+
+    s->bitstream_size=
+        s->bitstream_index= 0;
+}
+
+AVCodec shorten_decoder = {
+    "shorten",
+    CODEC_TYPE_AUDIO,
+    CODEC_ID_SHORTEN,
+    sizeof(ShortenContext),
+    shorten_decode_init,
+    NULL,
+    shorten_decode_close,
+    shorten_decode_frame,
+    .flush= shorten_flush,
+};

libavformat/raw.c

@@ -188,6 +188,21 @@ static int ac3_read_header(AVFormatContext *s,
     return 0;
 }
 
+static int shorten_read_header(AVFormatContext *s,
+                               AVFormatParameters *ap)
+{
+    AVStream *st;
+
+    st = av_new_stream(s, 0);
+    if (!st)
+        return AVERROR_NOMEM;
+    st->codec.codec_type = CODEC_TYPE_AUDIO;
+    st->codec.codec_id = CODEC_ID_SHORTEN;
+    st->need_parsing = 1;
+    /* the parameters will be extracted from the compressed bitstream */
+    return 0;
+}
+
 /* dts read */
 static int dts_read_header(AVFormatContext *s,
                            AVFormatParameters *ap)
@@ -295,6 +310,17 @@ static int h261_probe(AVProbeData *p)
     return 0;
 }
 
+AVInputFormat shorten_iformat = {
+    "shn",
+    "raw shn",
+    0,
+    NULL,
+    shorten_read_header,
+    raw_read_partial_packet,
+    raw_read_close,
+    .extensions = "shn",
+};
+
 AVInputFormat ac3_iformat = {
     "ac3",
     "raw ac3",
@@ -672,6 +698,9 @@ AVOutputFormat null_oformat = {
 
 int raw_init(void)
 {
+
+    av_register_input_format(&shorten_iformat);
+
     av_register_input_format(&ac3_iformat);
     av_register_output_format(&ac3_oformat);
 

libavformat/utils.c

@@ -1845,6 +1845,7 @@ int av_find_stream_info(AVFormatContext *ic)
              st->codec.codec_id == CODEC_ID_PGMYUV ||
              st->codec.codec_id == CODEC_ID_PBM ||
              st->codec.codec_id == CODEC_ID_PPM ||
+             st->codec.codec_id == CODEC_ID_SHORTEN ||
              (st->codec.codec_id == CODEC_ID_MPEG4 && !st->need_parsing)))
             try_decode_frame(st, pkt->data, pkt->size);