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-rw-r--r--ffmpeg1/libavcodec/yop.c257
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diff --git a/ffmpeg1/libavcodec/yop.c b/ffmpeg1/libavcodec/yop.c
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+/*
+ * Psygnosis YOP decoder
+ *
+ * Copyright (C) 2010 Mohamed Naufal Basheer <naufal11@gmail.com>
+ * derived from the code by
+ * Copyright (C) 2009 Thomas P. Higdon <thomas.p.higdon@gmail.com>
+ *
+ * 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 "libavutil/imgutils.h"
+
+#include "avcodec.h"
+#include "get_bits.h"
+#include "internal.h"
+
+typedef struct YopDecContext {
+ AVCodecContext *avctx;
+
+ int num_pal_colors;
+ int first_color[2];
+ int frame_data_length;
+
+ uint8_t *low_nibble;
+ uint8_t *srcptr;
+ uint8_t *src_end;
+ uint8_t *dstptr;
+ uint8_t *dstbuf;
+} YopDecContext;
+
+// These tables are taken directly from:
+// http://wiki.multimedia.cx/index.php?title=Psygnosis_YOP
+
+/**
+ * Lookup table for painting macroblocks. Bytes 0-2 of each entry contain
+ * the macroblock positions to be painted (taken as (0, B0, B1, B2)).
+ * Byte 3 contains the number of bytes consumed on the input,
+ * equal to max(bytes 0-2) + 1.
+ */
+static const uint8_t paint_lut[15][4] =
+ {{1, 2, 3, 4}, {1, 2, 0, 3},
+ {1, 2, 1, 3}, {1, 2, 2, 3},
+ {1, 0, 2, 3}, {1, 0, 0, 2},
+ {1, 0, 1, 2}, {1, 1, 2, 3},
+ {0, 1, 2, 3}, {0, 1, 0, 2},
+ {1, 1, 0, 2}, {0, 1, 1, 2},
+ {0, 0, 1, 2}, {0, 0, 0, 1},
+ {1, 1, 1, 2},
+ };
+
+/**
+ * Lookup table for copying macroblocks. Each entry contains the respective
+ * x and y pixel offset for the copy source.
+ */
+static const int8_t motion_vector[16][2] =
+ {{-4, -4}, {-2, -4},
+ { 0, -4}, { 2, -4},
+ {-4, -2}, {-4, 0},
+ {-3, -3}, {-1, -3},
+ { 1, -3}, { 3, -3},
+ {-3, -1}, {-2, -2},
+ { 0, -2}, { 2, -2},
+ { 4, -2}, {-2, 0},
+ };
+
+static av_cold int yop_decode_init(AVCodecContext *avctx)
+{
+ YopDecContext *s = avctx->priv_data;
+ s->avctx = avctx;
+
+ if (avctx->width & 1 || avctx->height & 1 ||
+ av_image_check_size(avctx->width, avctx->height, 0, avctx) < 0) {
+ av_log(avctx, AV_LOG_ERROR, "YOP has invalid dimensions\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ if (avctx->extradata_size < 3) {
+ av_log(avctx, AV_LOG_ERROR, "Missing or incomplete extradata.\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ avctx->pix_fmt = AV_PIX_FMT_PAL8;
+
+ s->num_pal_colors = avctx->extradata[0];
+ s->first_color[0] = avctx->extradata[1];
+ s->first_color[1] = avctx->extradata[2];
+
+ if (s->num_pal_colors + s->first_color[0] > 256 ||
+ s->num_pal_colors + s->first_color[1] > 256) {
+ av_log(avctx, AV_LOG_ERROR,
+ "Palette parameters invalid, header probably corrupt\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ return 0;
+}
+
+/**
+ * Paint a macroblock using the pattern in paint_lut.
+ * @param s codec context
+ * @param tag the tag that was in the nibble
+ */
+static int yop_paint_block(YopDecContext *s, int linesize, int tag)
+{
+ if (s->src_end - s->srcptr < paint_lut[tag][3]) {
+ av_log(s->avctx, AV_LOG_ERROR, "Packet too small.\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ s->dstptr[0] = s->srcptr[0];
+ s->dstptr[1] = s->srcptr[paint_lut[tag][0]];
+ s->dstptr[linesize] = s->srcptr[paint_lut[tag][1]];
+ s->dstptr[linesize + 1] = s->srcptr[paint_lut[tag][2]];
+
+ // The number of src bytes consumed is in the last part of the lut entry.
+ s->srcptr += paint_lut[tag][3];
+ return 0;
+}
+
+/**
+ * Copy a previously painted macroblock to the current_block.
+ * @param copy_tag the tag that was in the nibble
+ */
+static int yop_copy_previous_block(YopDecContext *s, int linesize, int copy_tag)
+{
+ uint8_t *bufptr;
+
+ // Calculate position for the copy source
+ bufptr = s->dstptr + motion_vector[copy_tag][0] +
+ linesize * motion_vector[copy_tag][1];
+ if (bufptr < s->dstbuf) {
+ av_log(s->avctx, AV_LOG_ERROR, "File probably corrupt\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ s->dstptr[0] = bufptr[0];
+ s->dstptr[1] = bufptr[1];
+ s->dstptr[linesize] = bufptr[linesize];
+ s->dstptr[linesize + 1] = bufptr[linesize + 1];
+
+ return 0;
+}
+
+/**
+ * Return the next nibble in sequence, consuming a new byte on the input
+ * only if necessary.
+ */
+static uint8_t yop_get_next_nibble(YopDecContext *s)
+{
+ int ret;
+
+ if (s->low_nibble) {
+ ret = *s->low_nibble & 0xf;
+ s->low_nibble = NULL;
+ }else {
+ s->low_nibble = s->srcptr++;
+ ret = *s->low_nibble >> 4;
+ }
+ return ret;
+}
+
+static int yop_decode_frame(AVCodecContext *avctx, void *data, int *got_frame,
+ AVPacket *avpkt)
+{
+ YopDecContext *s = avctx->priv_data;
+ AVFrame *frame = data;
+ int tag, firstcolor, is_odd_frame;
+ int ret, i, x, y;
+ uint32_t *palette;
+
+ if (avpkt->size < 4 + 3 * s->num_pal_colors) {
+ av_log(avctx, AV_LOG_ERROR, "Packet too small.\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ if ((ret = ff_get_buffer(avctx, frame, 0)) < 0)
+ return ret;
+
+ if (!avctx->frame_number)
+ memset(frame->data[1], 0, AVPALETTE_SIZE);
+
+ s->dstbuf = frame->data[0];
+ s->dstptr = frame->data[0];
+ s->srcptr = avpkt->data + 4;
+ s->src_end = avpkt->data + avpkt->size;
+ s->low_nibble = NULL;
+
+ is_odd_frame = avpkt->data[0];
+ if(is_odd_frame>1){
+ av_log(avctx, AV_LOG_ERROR, "frame is too odd %d\n", is_odd_frame);
+ return AVERROR_INVALIDDATA;
+ }
+ firstcolor = s->first_color[is_odd_frame];
+ palette = (uint32_t *)frame->data[1];
+
+ for (i = 0; i < s->num_pal_colors; i++, s->srcptr += 3) {
+ palette[i + firstcolor] = (s->srcptr[0] << 18) |
+ (s->srcptr[1] << 10) |
+ (s->srcptr[2] << 2);
+ palette[i + firstcolor] |= 0xFFU << 24 |
+ (palette[i + firstcolor] >> 6) & 0x30303;
+ }
+
+ frame->palette_has_changed = 1;
+
+ for (y = 0; y < avctx->height; y += 2) {
+ for (x = 0; x < avctx->width; x += 2) {
+ if (s->srcptr - avpkt->data >= avpkt->size) {
+ av_log(avctx, AV_LOG_ERROR, "Packet too small.\n");
+ return AVERROR_INVALIDDATA;
+ }
+
+ tag = yop_get_next_nibble(s);
+
+ if (tag != 0xf) {
+ ret = yop_paint_block(s, frame->linesize[0], tag);
+ if (ret < 0)
+ return ret;
+ } else {
+ tag = yop_get_next_nibble(s);
+ ret = yop_copy_previous_block(s, frame->linesize[0], tag);
+ if (ret < 0)
+ return ret;
+ }
+ s->dstptr += 2;
+ }
+ s->dstptr += 2*frame->linesize[0] - x;
+ }
+
+ *got_frame = 1;
+ return avpkt->size;
+}
+
+AVCodec ff_yop_decoder = {
+ .name = "yop",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .id = AV_CODEC_ID_YOP,
+ .priv_data_size = sizeof(YopDecContext),
+ .init = yop_decode_init,
+ .decode = yop_decode_frame,
+ .long_name = NULL_IF_CONFIG_SMALL("Psygnosis YOP Video"),
+};
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