diff ffmpeg/libavcodec/jvdec.c @ 10:6840f77b83aa

commit

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/ffmpeg/libavcodec/jvdec.c	Sun Apr 21 10:55:35 2013 +0200
@@ -0,0 +1,220 @@
+/*
+ * Bitmap Brothers JV video decoder
+ * Copyright (c) 2011 Peter Ross <[e-mail]>
+ *
+ * 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
+ * Bitmap Brothers JV video decoder
+ * @author Peter Ross <[e-mail]>
+ */
+
+#include "avcodec.h"
+#include "dsputil.h"
+#include "get_bits.h"
+#include "internal.h"
+#include "libavutil/intreadwrite.h"
+
+typedef struct JvContext {
+    DSPContext dsp;
+    AVFrame    frame;
+    uint32_t   palette[AVPALETTE_COUNT];
+    int        palette_has_changed;
+} JvContext;
+
+static av_cold int decode_init(AVCodecContext *avctx)
+{
+    JvContext *s = avctx->priv_data;
+    avctx->pix_fmt = AV_PIX_FMT_PAL8;
+    ff_dsputil_init(&s->dsp, avctx);
+    avcodec_get_frame_defaults(&s->frame);
+    return 0;
+}
+
+/**
+ * Decode 2x2 block
+ */
+static inline void decode2x2(GetBitContext *gb, uint8_t *dst, int linesize)
+{
+    int i, j, v[2];
+
+    switch (get_bits(gb, 2)) {
+    case 1:
+        v[0] = get_bits(gb, 8);
+        for (j = 0; j < 2; j++)
+            memset(dst + j*linesize, v[0], 2);
+        break;
+    case 2:
+        v[0] = get_bits(gb, 8);
+        v[1] = get_bits(gb, 8);
+        for (j = 0; j < 2; j++)
+            for (i = 0; i < 2; i++)
+                dst[j*linesize + i] = v[get_bits1(gb)];
+        break;
+    case 3:
+        for (j = 0; j < 2; j++)
+            for (i = 0; i < 2; i++)
+                dst[j*linesize + i] = get_bits(gb, 8);
+    }
+}
+
+/**
+ * Decode 4x4 block
+ */
+static inline void decode4x4(GetBitContext *gb, uint8_t *dst, int linesize)
+{
+    int i, j, v[2];
+
+    switch (get_bits(gb, 2)) {
+    case 1:
+        v[0] = get_bits(gb, 8);
+        for (j = 0; j < 4; j++)
+            memset(dst + j*linesize, v[0], 4);
+        break;
+    case 2:
+        v[0] = get_bits(gb, 8);
+        v[1] = get_bits(gb, 8);
+        for (j = 2; j >= 0; j -= 2) {
+            for (i = 0; i < 4; i++)
+                dst[j*linesize + i]     = v[get_bits1(gb)];
+            for (i = 0; i < 4; i++)
+                dst[(j+1)*linesize + i] = v[get_bits1(gb)];
+        }
+        break;
+    case 3:
+        for (j = 0; j < 4; j += 2)
+            for (i = 0; i < 4; i += 2)
+                decode2x2(gb, dst + j*linesize + i, linesize);
+    }
+}
+
+/**
+ * Decode 8x8 block
+ */
+static inline void decode8x8(GetBitContext *gb, uint8_t *dst, int linesize, DSPContext *dsp)
+{
+    int i, j, v[2];
+
+    switch (get_bits(gb, 2)) {
+    case 1:
+        v[0] = get_bits(gb, 8);
+        dsp->fill_block_tab[1](dst, v[0], linesize, 8);
+        break;
+    case 2:
+        v[0] = get_bits(gb, 8);
+        v[1] = get_bits(gb, 8);
+        for (j = 7; j >= 0; j--)
+            for (i = 0; i <  8; i++)
+                dst[j*linesize + i] = v[get_bits1(gb)];
+        break;
+    case 3:
+        for (j = 0; j < 8; j += 4)
+            for (i = 0; i < 8; i += 4)
+                decode4x4(gb, dst + j*linesize + i, linesize);
+    }
+}
+
+static int decode_frame(AVCodecContext *avctx,
+                        void *data, int *got_frame,
+                        AVPacket *avpkt)
+{
+    JvContext *s           = avctx->priv_data;
+    const uint8_t *buf     = avpkt->data;
+    const uint8_t *buf_end = buf + avpkt->size;
+    int video_size, video_type, i, j, ret;
+
+    if (avpkt->size < 6)
+        return AVERROR_INVALIDDATA;
+
+    video_size = AV_RL32(buf);
+    video_type = buf[4];
+    buf += 5;
+
+    if (video_size) {
+        if (video_size < 0 || video_size > avpkt->size - 5) {
+            av_log(avctx, AV_LOG_ERROR, "video size %d invalid\n", video_size);
+            return AVERROR_INVALIDDATA;
+        }
+        if ((ret = ff_reget_buffer(avctx, &s->frame)) < 0)
+            return ret;
+
+        if (video_type == 0 || video_type == 1) {
+            GetBitContext gb;
+            init_get_bits(&gb, buf, 8 * video_size);
+
+            for (j = 0; j < avctx->height; j += 8)
+                for (i = 0; i < avctx->width; i += 8)
+                    decode8x8(&gb, s->frame.data[0] + j*s->frame.linesize[0] + i,
+                              s->frame.linesize[0], &s->dsp);
+
+            buf += video_size;
+        } else if (video_type == 2) {
+            int v = *buf++;
+            for (j = 0; j < avctx->height; j++)
+                memset(s->frame.data[0] + j*s->frame.linesize[0], v, avctx->width);
+        } else {
+            av_log(avctx, AV_LOG_WARNING, "unsupported frame type %i\n", video_type);
+            return AVERROR_INVALIDDATA;
+        }
+    }
+
+    if (buf_end - buf >= AVPALETTE_COUNT * 3) {
+        for (i = 0; i < AVPALETTE_COUNT; i++) {
+            uint32_t pal = AV_RB24(buf);
+            s->palette[i] = 0xFFU << 24 | pal << 2 | ((pal >> 4) & 0x30303);
+            buf += 3;
+        }
+        s->palette_has_changed = 1;
+    }
+
+    if (video_size) {
+        s->frame.key_frame           = 1;
+        s->frame.pict_type           = AV_PICTURE_TYPE_I;
+        s->frame.palette_has_changed = s->palette_has_changed;
+        s->palette_has_changed       = 0;
+        memcpy(s->frame.data[1], s->palette, AVPALETTE_SIZE);
+
+        if ((ret = av_frame_ref(data, &s->frame)) < 0)
+            return ret;
+        *got_frame = 1;
+    }
+
+    return avpkt->size;
+}
+
+static av_cold int decode_close(AVCodecContext *avctx)
+{
+    JvContext *s = avctx->priv_data;
+
+    av_frame_unref(&s->frame);
+
+    return 0;
+}
+
+AVCodec ff_jv_decoder = {
+    .name           = "jv",
+    .long_name      = NULL_IF_CONFIG_SMALL("Bitmap Brothers JV video"),
+    .type           = AVMEDIA_TYPE_VIDEO,
+    .id             = AV_CODEC_ID_JV,
+    .priv_data_size = sizeof(JvContext),
+    .init           = decode_init,
+    .close          = decode_close,
+    .decode         = decode_frame,
+    .capabilities   = CODEC_CAP_DR1,
+};