[FFmpeg-devel] [PATCH v3] Canopus Lossless decoder

Derek Buitenhuis derek.buitenhuis at gmail.com
Sun Jul 29 00:28:50 CEST 2012


At the moment it only does BGR24, but I plan to add the rest after.

Signed-off-by: Derek Buitenhuis <derek.buitenhuis at gmail.com>
---
 Changelog              |    1 +
 MAINTAINERS            |    1 +
 doc/general.texi       |    1 +
 libavcodec/Makefile    |    1 +
 libavcodec/allcodecs.c |    1 +
 libavcodec/avcodec.h   |    1 +
 libavcodec/cllc.c      |  290 ++++++++++++++++++++++++++++++++++++++++++++++++
 libavcodec/version.h   |    2 +-
 libavformat/riff.c     |    1 +
 9 files changed, 298 insertions(+), 1 deletion(-)
 create mode 100644 libavcodec/cllc.c

diff --git a/Changelog b/Changelog
index 79a8f4c..813116a 100644
--- a/Changelog
+++ b/Changelog
@@ -38,6 +38,7 @@ version next:
 - alphaextract and alphamerge filters
 - concat filter
 - flite filter
+- Canopus Lossless Codec decoder
 
 
 version 0.11:
diff --git a/MAINTAINERS b/MAINTAINERS
index 1a9f29b..f265907 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -132,6 +132,7 @@ Codecs:
   celp_filters.*                        Vitor Sessak
   cinepak.c                             Roberto Togni
   cljr                                  Alex Beregszaszi
+  cllc.c                                Derek Buitenhuis
   cook.c, cookdata.h                    Benjamin Larsson
   crystalhd.c                           Philip Langdale
   cscd.c                                Reimar Doeffinger
diff --git a/doc/general.texi b/doc/general.texi
index 1849aec..ebbe189 100644
--- a/doc/general.texi
+++ b/doc/general.texi
@@ -501,6 +501,7 @@ following image formats are supported:
 @item Delphine Software International CIN video  @tab     @tab  X
     @tab Codec used in Delphine Software International games.
 @item Discworld II BMV Video @tab     @tab  X
+ at item Canopus Lossless Codec @tab     @tab  X
 @item Cinepak                @tab     @tab  X
 @item Cirrus Logic AccuPak   @tab  X  @tab  X
     @tab fourcc: CLJR
diff --git a/libavcodec/Makefile b/libavcodec/Makefile
index b4138e8..bb9aa9a 100644
--- a/libavcodec/Makefile
+++ b/libavcodec/Makefile
@@ -131,6 +131,7 @@ OBJS-$(CONFIG_CDXL_DECODER)            += cdxl.o
 OBJS-$(CONFIG_CINEPAK_DECODER)         += cinepak.o
 OBJS-$(CONFIG_CLJR_DECODER)            += cljr.o
 OBJS-$(CONFIG_CLJR_ENCODER)            += cljr.o
+OBJS-$(CONFIG_CLLC_DECODER)            += cllc.o
 OBJS-$(CONFIG_COOK_DECODER)            += cook.o
 OBJS-$(CONFIG_CSCD_DECODER)            += cscd.o
 OBJS-$(CONFIG_CYUV_DECODER)            += cyuv.o
diff --git a/libavcodec/allcodecs.c b/libavcodec/allcodecs.c
index 6bcc3c2..43c6c16 100644
--- a/libavcodec/allcodecs.c
+++ b/libavcodec/allcodecs.c
@@ -94,6 +94,7 @@ void avcodec_register_all(void)
     REGISTER_DECODER (CDXL, cdxl);
     REGISTER_DECODER (CINEPAK, cinepak);
     REGISTER_ENCDEC  (CLJR, cljr);
+    REGISTER_DECODER (CLLC, cllc);
     REGISTER_DECODER (CSCD, cscd);
     REGISTER_DECODER (CYUV, cyuv);
     REGISTER_DECODER (DFA, dfa);
diff --git a/libavcodec/avcodec.h b/libavcodec/avcodec.h
index edbc59b..b7f4a41 100644
--- a/libavcodec/avcodec.h
+++ b/libavcodec/avcodec.h
@@ -274,6 +274,7 @@ enum CodecID {
     CODEC_ID_YUV4       = MKBETAG('Y','U','V','4'),
     CODEC_ID_SANM       = MKBETAG('S','A','N','M'),
     CODEC_ID_PAF_VIDEO  = MKBETAG('P','A','F','V'),
+    CODEC_ID_CLLC       = MKBETAG('C','L','L','C'),
 
     /* various PCM "codecs" */
     CODEC_ID_FIRST_AUDIO = 0x10000,     ///< A dummy id pointing at the start of audio codecs
diff --git a/libavcodec/cllc.c b/libavcodec/cllc.c
new file mode 100644
index 0000000..586361d
--- /dev/null
+++ b/libavcodec/cllc.c
@@ -0,0 +1,290 @@
+/*
+ * Canopus Lossless Codec decoder
+ *
+ * Copyright (c) 2012 Derek Buitenhuis
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg 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 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg 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 FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include "libavutil/intreadwrite.h"
+#include "dsputil.h"
+#include "get_bits.h"
+#include "avcodec.h"
+
+typedef struct CLLCContext {
+    DSPContext dsp;
+    AVCodecContext *avctx;
+
+    uint8_t *swapped_buf;
+    int      swapped_buf_size;
+    int8_t   code_table[3][32768];
+} CLLCContext;
+
+/*
+ * We could use ff_init_vlc_sparse and get_vlc2, but it would
+ * provide basolutely no benefit in this case. The lookup table
+ * size is known and we can easily reuse the same buffer instead
+ * of constructing one every frame. Using these two functions
+ * would only result in more complex code, with no tangible
+ * benefit.
+ */
+static int read_code_table(CLLCContext *ctx, GetBitContext *gb,
+                           int8_t *code_table)
+{
+    int num_lens, num_codes;
+    int prefix, symbol, sym_shift;
+    int i, j, k;
+
+    sym_shift = 13;
+    prefix    = 0;
+
+    num_lens = get_bits(gb, 5);
+
+    for (i = 0; i < num_lens; i++) {
+        num_codes = get_bits(gb, 9);
+
+        for (j = num_codes; j > 0; j--) {
+            symbol = get_bits(gb, 8);
+
+            /* Make sure we don't overflow */
+            if (prefix + 1 << sym_shift > 1 << 14) {
+                av_log(ctx->avctx, AV_LOG_ERROR, "Could not read VLCs.\n");
+                return AVERROR_INVALIDDATA;
+            }
+
+            /* Populate the table with symbols */
+            for (k = prefix << sym_shift; k < prefix + 1 << sym_shift; k++) {
+                code_table[2 * k]     = symbol;
+                code_table[2 * k + 1] = i + 1;
+            }
+
+            prefix++;
+        }
+
+        sym_shift--;
+        prefix <<= 1;
+    }
+
+    return num_lens;
+}
+
+static int read_line(CLLCContext *ctx, GetBitContext *gb, int *top_left,
+                     int8_t *code_table, uint8_t *outbuf)
+{
+    uint8_t *dst;
+    int pred, skip;
+    int i;
+
+    dst  = outbuf;
+    pred = *top_left;
+
+    /* Simultaniously read and restore the line */
+    for (i = 0; i < ctx->avctx->width; i++) {
+        pred += code_table[2 * show_bits(gb, 14)];
+        skip  = code_table[2 * show_bits(gb, 14) + 1];
+
+        skip_bits(gb, skip);
+
+        dst[0] = pred;
+        dst   += 3;
+    }
+
+    /* Stash the first pixel */
+    *top_left = dst[-3 * ctx->avctx->width];
+
+    return 0;
+}
+
+static int decode_bgr24_frame(CLLCContext *ctx, GetBitContext *gb, AVFrame *pic)
+{
+    AVCodecContext *avctx = ctx->avctx;
+    uint8_t *dst;
+    int pred[3];
+    int ret;
+    int i, j;
+
+    pred[0] = 0x80;
+    pred[1] = 0x80;
+    pred[2] = 0x80;
+
+    dst = pic->data[0] + 5;
+
+    skip_bits(gb, 16);
+
+    /* Read in code table for each plane */
+    for (i = 0; i < 3; i++) {
+        ret = read_code_table(ctx, gb, ctx->code_table[i]);
+        if (ret <= 0) {
+            av_log(ctx->avctx, AV_LOG_ERROR,
+                   "Could not read code table %d.\n", i);
+            return ret;
+        }
+    }
+
+    /* Read in and restore every line */
+    for (i = avctx->height; i > 0; i--) {
+        for (j = 0; j < 3; j++)
+            read_line(ctx, gb, &pred[j], ctx->code_table[j], dst - j);
+
+        dst += pic->linesize[0];
+    }
+
+    return 0;
+}
+
+static int cllc_decode_frame(AVCodecContext *avctx, void *data,
+                             int *got_picture_ptr, AVPacket *avpkt)
+{
+    CLLCContext *ctx = avctx->priv_data;
+    AVFrame *pic = avctx->coded_frame;
+    uint8_t *src = avpkt->data;
+    uint8_t *swapped_buf_new;
+    uint32_t info_tag, info_offset;
+    GetBitContext gb;
+    int coding_type, ret;
+
+    if (pic->data[0])
+        avctx->release_buffer(avctx, pic);
+
+    pic->reference = 0;
+
+    /* Make sure our bswap16'd buffer is big enough */
+    swapped_buf_new = av_fast_realloc(ctx->swapped_buf,
+                                      &ctx->swapped_buf_size, avpkt->size);
+    if (!swapped_buf_new) {
+        av_log(avctx, AV_LOG_ERROR, "Could not realloc swapepd buffer.\n");
+        return AVERROR(ENOMEM);
+    }
+    ctx->swapped_buf = swapped_buf_new;
+
+    /* Skip the INFO header if present */
+    info_offset = 0;
+    info_tag    = AV_RL32(src);
+    if (info_tag == MKTAG('I', 'N', 'F', 'O')) {
+        info_offset = AV_RL32(src + 4);
+        if (info_offset > UINT32_MAX - 8 || info_offset > avpkt->size - 8) {
+            av_log(avctx, AV_LOG_ERROR,
+                   "Invalid INFO header offset: 0x%08X is too large.\n",
+                   info_offset);
+            return AVERROR_INVALIDDATA;
+        }
+
+        info_offset += 8;
+        src         += info_offset;
+
+        av_log(avctx, AV_LOG_DEBUG, "Skipping INFO chunk.\n");
+    }
+
+    /* bswap16 the buffer since CLLC's bitreader works in 16-bit WORDS */
+    ctx->dsp.bswap16_buf((uint16_t *) ctx->swapped_buf, (uint16_t *) src,
+                         (avpkt->size - info_offset) / 2);
+
+    init_get_bits(&gb, ctx->swapped_buf, (avpkt->size - info_offset) * 8);
+
+    /*
+     * Read in coding type. The types are as follows:
+     *
+     * 0 - YUY2
+     * 1 - BGR24 (Triples)
+     * 2 - BGR24 (Quads)
+     * 3 - BGRA
+     */
+    coding_type = (AV_RL32(src) >> 8) & 0xFF;
+    av_log(avctx, AV_LOG_DEBUG, "Frame coding type: %d\n", coding_type);
+
+    switch (coding_type) {
+    case 1:
+        avctx->pix_fmt             = PIX_FMT_BGR24;
+        avctx->bits_per_raw_sample = 8;
+
+        if (avctx->get_buffer(avctx, pic) < 0) {
+            av_log(avctx, AV_LOG_ERROR, "Could not allocate buffer.\n");
+            return AVERROR(ENOMEM);
+        }
+
+        ret = decode_bgr24_frame(ctx, &gb, pic);
+        if (ret < 0)
+            return ret;
+
+        break;
+    default:
+        av_log(avctx, AV_LOG_ERROR, "Unknown coding type: %d\n.", coding_type);
+        return AVERROR_INVALIDDATA;
+    }
+
+    pic->key_frame = 1;
+    pic->pict_type = AV_PICTURE_TYPE_I;
+
+    *got_picture_ptr = 1;
+    *(AVFrame *)data = *pic;
+
+    return avpkt->size;
+}
+
+static av_cold int cllc_decode_close(AVCodecContext *avctx)
+{
+    CLLCContext *ctx = avctx->priv_data;
+
+    if (avctx->coded_frame->data[0])
+        avctx->release_buffer(avctx, avctx->coded_frame);
+
+    if (avctx->coded_frame)
+        av_freep(&avctx->coded_frame);
+
+    if (ctx->swapped_buf)
+        av_freep(&ctx->swapped_buf);
+
+    return 0;
+}
+
+static av_cold int cllc_decode_init(AVCodecContext *avctx)
+{
+    CLLCContext *ctx = avctx->priv_data;
+
+    /* Stash for later use */
+    ctx->avctx = avctx;
+
+    ff_dsputil_init(&ctx->dsp, avctx);
+
+    avctx->coded_frame = avcodec_alloc_frame();
+    if (!avctx->coded_frame) {
+        av_log(avctx, AV_LOG_ERROR, "Could not allocate frame.\n");
+        return AVERROR(ENOMEM);
+    }
+
+    ctx->swapped_buf = av_malloc(avctx->width * avctx->height * 3);
+    if (!ctx->swapped_buf) {
+        cllc_decode_close(avctx);
+        av_log(avctx, AV_LOG_ERROR,
+               "Could not allocate swapped buffer frame.\n");
+        return AVERROR(ENOMEM);
+    }
+
+    return 0;
+}
+
+AVCodec ff_cllc_decoder = {
+    .name           = "cllc",
+    .type           = AVMEDIA_TYPE_VIDEO,
+    .id             = CODEC_ID_CLLC,
+    .priv_data_size = sizeof(CLLCContext),
+    .init           = cllc_decode_init,
+    .decode         = cllc_decode_frame,
+    .close          = cllc_decode_close,
+    .capabilities   = CODEC_CAP_DR1,
+    .long_name      = NULL_IF_CONFIG_SMALL("Canopus Lossless Codec"),
+};
diff --git a/libavcodec/version.h b/libavcodec/version.h
index 81d731c..e8cafeb 100644
--- a/libavcodec/version.h
+++ b/libavcodec/version.h
@@ -27,7 +27,7 @@
  */
 
 #define LIBAVCODEC_VERSION_MAJOR 54
-#define LIBAVCODEC_VERSION_MINOR  45
+#define LIBAVCODEC_VERSION_MINOR 46
 #define LIBAVCODEC_VERSION_MICRO 100
 
 #define LIBAVCODEC_VERSION_INT  AV_VERSION_INT(LIBAVCODEC_VERSION_MAJOR, \
diff --git a/libavformat/riff.c b/libavformat/riff.c
index 04419ed..bf14c45 100644
--- a/libavformat/riff.c
+++ b/libavformat/riff.c
@@ -315,6 +315,7 @@ const AVCodecTag ff_codec_bmp_tags[] = {
     { CODEC_ID_MSA1,         MKTAG('M', 'S', 'A', '1') },
     { CODEC_ID_TSCC2,        MKTAG('T', 'S', 'C', '2') },
     { CODEC_ID_MTS2,         MKTAG('M', 'T', 'S', '2') },
+    { CODEC_ID_CLLC,         MKTAG('C', 'L', 'L', 'C') },
     { CODEC_ID_NONE,         0 }
 };
 
-- 
1.7.10.4



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