support for Tiertex .seq files demuxing/video decoding, by Gregory Montoir %cyx A users P sourceforge P net%

Originally committed as revision 6672 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 232 insertions, 0 deletions

diff --git a/libavcodec/tiertexseqv.c b/libavcodec/tiertexseqv.c
new file mode 100644
index 0000000000..ca3baf09ef
--- /dev/null
+++ b/libavcodec/tiertexseqv.c
@@ -0,0 +1,232 @@
+/*
+ * Tiertex Limited SEQ Video Decoder
+ * Copyright (c) 2006 Gregory Montoir (cyx@users.sourceforge.net)
+ *
+ * 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
+ */
+
+/**
+ * @file tiertexseqv.c
+ * Tiertex Limited SEQ video decoder
+ */
+
+#include "avcodec.h"
+#include "common.h"
+#define ALT_BITSTREAM_READER_LE
+#include "bitstream.h"
+
+
+typedef struct SeqVideoContext {
+    AVCodecContext *avctx;
+    AVFrame frame;
+    unsigned int palette[256];
+    unsigned char block[8 * 8];
+} SeqVideoContext;
+
+
+static unsigned char *seq_unpack_rle_block(unsigned char *src, unsigned char *dst, int dst_size)
+{
+    int i, len, sz;
+    GetBitContext gb;
+    int code_table[64];
+
+    /* get the rle codes (at most 64 bytes) */
+    init_get_bits(&gb, src, 64 * 8);
+    for (i = 0, sz = 0; i < 64 && sz < dst_size; i++) {
+        code_table[i] = get_sbits(&gb, 4);
+        sz += FFABS(code_table[i]);
+    }
+    src += (get_bits_count(&gb) + 7) / 8;
+
+    /* do the rle unpacking */
+    for (i = 0; i < 64 && dst_size > 0; i++) {
+        len = code_table[i];
+        if (len < 0) {
+            len = -len;
+            memset(dst, *src++, FFMIN(len, dst_size));
+        } else {
+            memcpy(dst, src, FFMIN(len, dst_size));
+            src += len;
+        }
+        dst += len;
+        dst_size -= len;
+    }
+    return src;
+}
+
+static unsigned char *seq_decode_op1(SeqVideoContext *seq, unsigned char *src, unsigned char *dst)
+{
+    unsigned char *color_table;
+    int b, i, len, bits;
+    GetBitContext gb;
+
+    len = *src++;
+    if (len & 0x80) {
+        switch (len & 3) {
+        case 1:
+            src = seq_unpack_rle_block(src, seq->block, sizeof(seq->block));
+            for (b = 0; b < 8; b++) {
+                memcpy(dst, &seq->block[b * 8], 8);
+                dst += seq->frame.linesize[0];
+            }
+            break;
+        case 2:
+            src = seq_unpack_rle_block(src, seq->block, sizeof(seq->block));
+            for (i = 0; i < 8; i++) {
+                for (b = 0; b < 8; b++)
+                    dst[b * seq->frame.linesize[0]] = seq->block[i * 8 + b];
+                ++dst;
+            }
+            break;
+        }
+    } else {
+        color_table = src;
+        src += len;
+        bits = ff_log2_tab[len - 1] + 1;
+        init_get_bits(&gb, src, bits * 8 * 8); src += bits * 8;
+        for (b = 0; b < 8; b++) {
+            for (i = 0; i < 8; i++)
+                dst[i] = color_table[get_bits(&gb, bits)];
+            dst += seq->frame.linesize[0];
+        }
+    }
+
+    return src;
+}
+
+static unsigned char *seq_decode_op2(SeqVideoContext *seq, unsigned char *src, unsigned char *dst)
+{
+    int i;
+
+    for (i = 0; i < 8; i++) {
+        memcpy(dst, src, 8);
+        src += 8;
+        dst += seq->frame.linesize[0];
+    }
+
+    return src;
+}
+
+static unsigned char *seq_decode_op3(SeqVideoContext *seq, unsigned char *src, unsigned char *dst)
+{
+    int pos, offset;
+
+    do {
+        pos = *src++;
+        offset = ((pos >> 3) & 7) * seq->frame.linesize[0] + (pos & 7);
+        dst[offset] = *src++;
+    } while (!(pos & 0x80));
+
+    return src;
+}
+
+static void seqvideo_decode(SeqVideoContext *seq, unsigned char *data, int data_size)
+{
+    GetBitContext gb;
+    int flags, i, j, x, y, op;
+    unsigned char c[3];
+    unsigned char *dst;
+
+    flags = *data++;
+
+    if (flags & 1) {
+        for (i = 0; i < 256; i++) {
+            for (j = 0; j < 3; j++, data++)
+                c[j] = (*data << 2) | (*data >> 4);
+            seq->palette[i] = (c[0] << 16) | (c[1] << 8) | c[2];
+        }
+        memcpy(seq->frame.data[1], seq->palette, sizeof(seq->palette));
+        seq->frame.palette_has_changed = 1;
+    }
+
+    if (flags & 2) {
+        init_get_bits(&gb, data, 128 * 8); data += 128;
+        for (y = 0; y < 128; y += 8)
+            for (x = 0; x < 256; x += 8) {
+                dst = &seq->frame.data[0][y * seq->frame.linesize[0] + x];
+                op = get_bits(&gb, 2);
+                switch (op) {
+                case 1:
+                    data = seq_decode_op1(seq, data, dst);
+                    break;
+                case 2:
+                    data = seq_decode_op2(seq, data, dst);
+                    break;
+                case 3:
+                    data = seq_decode_op3(seq, data, dst);
+                    break;
+                }
+            }
+    }
+}
+
+static int seqvideo_decode_init(AVCodecContext *avctx)
+{
+    SeqVideoContext *seq = (SeqVideoContext *)avctx->priv_data;
+
+    seq->avctx = avctx;
+    avctx->pix_fmt = PIX_FMT_PAL8;
+    avctx->has_b_frames = 0;
+
+    seq->frame.data[0] = NULL;
+
+    return 0;
+}
+
+static int seqvideo_decode_frame(AVCodecContext *avctx,
+                                 void *data, int *data_size,
+                                 uint8_t *buf, int buf_size)
+{
+
+    SeqVideoContext *seq = (SeqVideoContext *)avctx->priv_data;
+
+    seq->frame.reference = 1;
+    seq->frame.buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE | FF_BUFFER_HINTS_REUSABLE;
+    if (avctx->reget_buffer(avctx, &seq->frame)) {
+        av_log(seq->avctx, AV_LOG_ERROR, "tiertexseqvideo: reget_buffer() failed\n");
+        return -1;
+    }
+
+    seqvideo_decode(seq, buf, buf_size);
+
+    *data_size = sizeof(AVFrame);
+    *(AVFrame *)data = seq->frame;
+
+    return buf_size;
+}
+
+static int seqvideo_decode_end(AVCodecContext *avctx)
+{
+    SeqVideoContext *seq = (SeqVideoContext *)avctx->priv_data;
+
+    if (seq->frame.data[0])
+        avctx->release_buffer(avctx, &seq->frame);
+
+    return 0;
+}
+
+AVCodec tiertexseqvideo_decoder = {
+    "tiertexseqvideo",
+    CODEC_TYPE_VIDEO,
+    CODEC_ID_TIERTEXSEQVIDEO,
+    sizeof(SeqVideoContext),
+    seqvideo_decode_init,
+    NULL,
+    seqvideo_decode_end,
+    seqvideo_decode_frame,
+    CODEC_CAP_DR1,
+};