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-rw-r--r--ffmpeg1/libavcodec/mdec.c254
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diff --git a/ffmpeg1/libavcodec/mdec.c b/ffmpeg1/libavcodec/mdec.c
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+/*
+ * Sony PlayStation MDEC (Motion DECoder)
+ * Copyright (c) 2003 Michael Niedermayer
+ *
+ * based upon code from Sebastian Jedruszkiewicz <elf@frogger.rules.pl>
+ *
+ * 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
+ * Sony PlayStation MDEC (Motion DECoder)
+ * This is very similar to intra-only MPEG-1.
+ */
+
+#include "avcodec.h"
+#include "mpegvideo.h"
+#include "mpeg12.h"
+#include "thread.h"
+
+typedef struct MDECContext {
+ AVCodecContext *avctx;
+ DSPContext dsp;
+ ThreadFrame frame;
+ GetBitContext gb;
+ ScanTable scantable;
+ int version;
+ int qscale;
+ int last_dc[3];
+ int mb_width;
+ int mb_height;
+ int mb_x, mb_y;
+ DECLARE_ALIGNED(16, int16_t, block)[6][64];
+ uint8_t *bitstream_buffer;
+ unsigned int bitstream_buffer_size;
+ int block_last_index[6];
+} MDECContext;
+
+//very similar to MPEG-1
+static inline int mdec_decode_block_intra(MDECContext *a, int16_t *block, int n)
+{
+ int level, diff, i, j, run;
+ int component;
+ RLTable *rl = &ff_rl_mpeg1;
+ uint8_t * const scantable = a->scantable.permutated;
+ const uint16_t *quant_matrix = ff_mpeg1_default_intra_matrix;
+ const int qscale = a->qscale;
+
+ /* DC coefficient */
+ if (a->version == 2) {
+ block[0] = 2 * get_sbits(&a->gb, 10) + 1024;
+ } else {
+ component = (n <= 3 ? 0 : n - 4 + 1);
+ diff = decode_dc(&a->gb, component);
+ if (diff >= 0xffff)
+ return AVERROR_INVALIDDATA;
+ a->last_dc[component] += diff;
+ block[0] = a->last_dc[component] << 3;
+ }
+
+ i = 0;
+ {
+ OPEN_READER(re, &a->gb);
+ /* now quantify & encode AC coefficients */
+ for (;;) {
+ UPDATE_CACHE(re, &a->gb);
+ GET_RL_VLC(level, run, re, &a->gb, rl->rl_vlc[0], TEX_VLC_BITS, 2, 0);
+
+ if (level == 127) {
+ break;
+ } else if (level != 0) {
+ i += run;
+ j = scantable[i];
+ level = (level * qscale * quant_matrix[j]) >> 3;
+ level = (level ^ SHOW_SBITS(re, &a->gb, 1)) - SHOW_SBITS(re, &a->gb, 1);
+ LAST_SKIP_BITS(re, &a->gb, 1);
+ } else {
+ /* escape */
+ run = SHOW_UBITS(re, &a->gb, 6)+1; LAST_SKIP_BITS(re, &a->gb, 6);
+ UPDATE_CACHE(re, &a->gb);
+ level = SHOW_SBITS(re, &a->gb, 10); SKIP_BITS(re, &a->gb, 10);
+ i += run;
+ j = scantable[i];
+ if (level < 0) {
+ level = -level;
+ level = (level * qscale * quant_matrix[j]) >> 3;
+ level = (level - 1) | 1;
+ level = -level;
+ } else {
+ level = (level * qscale * quant_matrix[j]) >> 3;
+ level = (level - 1) | 1;
+ }
+ }
+ if (i > 63) {
+ av_log(a->avctx, AV_LOG_ERROR, "ac-tex damaged at %d %d\n", a->mb_x, a->mb_y);
+ return AVERROR_INVALIDDATA;
+ }
+
+ block[j] = level;
+ }
+ CLOSE_READER(re, &a->gb);
+ }
+ a->block_last_index[n] = i;
+ return 0;
+}
+
+static inline int decode_mb(MDECContext *a, int16_t block[6][64])
+{
+ int i, ret;
+ const int block_index[6] = { 5, 4, 0, 1, 2, 3 };
+
+ a->dsp.clear_blocks(block[0]);
+
+ for (i = 0; i < 6; i++) {
+ if ((ret = mdec_decode_block_intra(a, block[block_index[i]],
+ block_index[i])) < 0)
+ return ret;
+ if (get_bits_left(&a->gb) < 0)
+ return AVERROR_INVALIDDATA;
+ }
+ return 0;
+}
+
+static inline void idct_put(MDECContext *a, AVFrame *frame, int mb_x, int mb_y)
+{
+ int16_t (*block)[64] = a->block;
+ int linesize = frame->linesize[0];
+
+ uint8_t *dest_y = frame->data[0] + (mb_y * 16* linesize ) + mb_x * 16;
+ uint8_t *dest_cb = frame->data[1] + (mb_y * 8 * frame->linesize[1]) + mb_x * 8;
+ uint8_t *dest_cr = frame->data[2] + (mb_y * 8 * frame->linesize[2]) + mb_x * 8;
+
+ a->dsp.idct_put(dest_y, linesize, block[0]);
+ a->dsp.idct_put(dest_y + 8, linesize, block[1]);
+ a->dsp.idct_put(dest_y + 8 * linesize, linesize, block[2]);
+ a->dsp.idct_put(dest_y + 8 * linesize + 8, linesize, block[3]);
+
+ if (!(a->avctx->flags & CODEC_FLAG_GRAY)) {
+ a->dsp.idct_put(dest_cb, frame->linesize[1], block[4]);
+ a->dsp.idct_put(dest_cr, frame->linesize[2], block[5]);
+ }
+}
+
+static int decode_frame(AVCodecContext *avctx,
+ void *data, int *got_frame,
+ AVPacket *avpkt)
+{
+ MDECContext * const a = avctx->priv_data;
+ const uint8_t *buf = avpkt->data;
+ int buf_size = avpkt->size;
+ ThreadFrame frame = { .f = data };
+ int i, ret;
+
+ if ((ret = ff_thread_get_buffer(avctx, &frame, 0)) < 0)
+ return ret;
+ frame.f->pict_type = AV_PICTURE_TYPE_I;
+ frame.f->key_frame = 1;
+
+ av_fast_malloc(&a->bitstream_buffer, &a->bitstream_buffer_size, buf_size + FF_INPUT_BUFFER_PADDING_SIZE);
+ if (!a->bitstream_buffer)
+ return AVERROR(ENOMEM);
+ for (i = 0; i < buf_size; i += 2) {
+ a->bitstream_buffer[i] = buf[i + 1];
+ a->bitstream_buffer[i + 1] = buf[i];
+ }
+ init_get_bits(&a->gb, a->bitstream_buffer, buf_size * 8);
+
+ /* skip over 4 preamble bytes in stream (typically 0xXX 0xXX 0x00 0x38) */
+ skip_bits(&a->gb, 32);
+
+ a->qscale = get_bits(&a->gb, 16);
+ a->version = get_bits(&a->gb, 16);
+
+ a->last_dc[0] = a->last_dc[1] = a->last_dc[2] = 128;
+
+ for (a->mb_x = 0; a->mb_x < a->mb_width; a->mb_x++) {
+ for (a->mb_y = 0; a->mb_y < a->mb_height; a->mb_y++) {
+ if ((ret = decode_mb(a, a->block)) < 0)
+ return ret;
+
+ idct_put(a, frame.f, a->mb_x, a->mb_y);
+ }
+ }
+
+ *got_frame = 1;
+
+ return (get_bits_count(&a->gb) + 31) / 32 * 4;
+}
+
+static av_cold int decode_init(AVCodecContext *avctx)
+{
+ MDECContext * const a = avctx->priv_data;
+
+ a->mb_width = (avctx->coded_width + 15) / 16;
+ a->mb_height = (avctx->coded_height + 15) / 16;
+
+ a->avctx = avctx;
+
+ ff_dsputil_init(&a->dsp, avctx);
+ ff_mpeg12_init_vlcs();
+ ff_init_scantable(a->dsp.idct_permutation, &a->scantable, ff_zigzag_direct);
+
+ if (avctx->idct_algo == FF_IDCT_AUTO)
+ avctx->idct_algo = FF_IDCT_SIMPLE;
+ avctx->pix_fmt = AV_PIX_FMT_YUVJ420P;
+
+ return 0;
+}
+
+static av_cold int decode_init_thread_copy(AVCodecContext *avctx)
+{
+ MDECContext * const a = avctx->priv_data;
+
+ a->avctx = avctx;
+
+ return 0;
+}
+
+static av_cold int decode_end(AVCodecContext *avctx)
+{
+ MDECContext * const a = avctx->priv_data;
+
+ av_freep(&a->bitstream_buffer);
+ a->bitstream_buffer_size = 0;
+
+ return 0;
+}
+
+AVCodec ff_mdec_decoder = {
+ .name = "mdec",
+ .type = AVMEDIA_TYPE_VIDEO,
+ .id = AV_CODEC_ID_MDEC,
+ .priv_data_size = sizeof(MDECContext),
+ .init = decode_init,
+ .close = decode_end,
+ .decode = decode_frame,
+ .capabilities = CODEC_CAP_DR1 | CODEC_CAP_FRAME_THREADS,
+ .long_name = NULL_IF_CONFIG_SMALL("Sony PlayStation MDEC (Motion DECoder)"),
+ .init_thread_copy = ONLY_IF_THREADS_ENABLED(decode_init_thread_copy)
+};
generated by cgit v1.2.3 (git 2.39.1) at 2025-12-06 16:30:35 +0000