Interplay C93 demuxer and video decoder

patch by Anssi Hannula, anssi.hannula gmail com

Originally committed as revision 8643 to svn://svn.ffmpeg.org/ffmpeg/trunk

Changelog

@@ -77,6 +77,7 @@ version <next>
 - DNxHD decoder
 - Gamecube movie (.THP) playback system
 - Blackfin optimizations
+- Interplay C93 demuxer and video decoder
 
 version 0.4.9-pre1:
 

doc/ffmpeg-doc.texi

@@ -903,6 +903,8 @@ library:
 different game cutscenes repacked for use with ScummVM.
 @item THP @tab    @tab X
 @tab Used on the Nintendo GameCube (video only)
+@item C93 @tab    @tab X
+@tab Used in the game Cyberia from Interplay.
 @end multitable
 
 @code{X} means that encoding (resp. decoding) is supported.
@@ -1012,6 +1014,7 @@ following image formats are supported:
 @item Tiertex Seq Video      @tab     @tab  X @tab Codec used in DOS CDROM FlashBack game.
 @item DXA Video              @tab     @tab  X @tab Codec originally used in Feeble Files game.
 @item AVID DNxHD             @tab     @tab  X @tab aka SMPTE VC3
+@item C93 Video              @tab     @tab  X @tab Codec used in Cyberia game.
 @end multitable
 
 @code{X} means that encoding (resp. decoding) is supported.

libavcodec/Makefile

@@ -56,6 +56,7 @@ OBJS-$(CONFIG_ASV2_ENCODER)            += asv1.o
 OBJS-$(CONFIG_AVS_DECODER)             += avs.o
 OBJS-$(CONFIG_BMP_DECODER)             += bmp.o
 OBJS-$(CONFIG_BMP_ENCODER)             += bmpenc.o
+OBJS-$(CONFIG_C93_DECODER)             += c93.o
 OBJS-$(CONFIG_CAVS_DECODER)            += cavs.o cavsdsp.o
 OBJS-$(CONFIG_CINEPAK_DECODER)         += cinepak.o
 OBJS-$(CONFIG_CLJR_DECODER)            += cljr.o

libavcodec/allcodecs.c

@@ -59,6 +59,7 @@ void avcodec_register_all(void)
     REGISTER_ENCDEC (ASV2, asv2);
     REGISTER_DECODER(AVS, avs);
     REGISTER_ENCDEC (BMP, bmp);
+    REGISTER_DECODER(C93, c93);
     REGISTER_DECODER(CAVS, cavs);
     REGISTER_DECODER(CINEPAK, cinepak);
     REGISTER_DECODER(CLJR, cljr);

libavcodec/avcodec.h

@@ -160,6 +160,7 @@ enum CodecID {
     CODEC_ID_DNXHD,
     CODEC_ID_THP,
     CODEC_ID_SGI,
+    CODEC_ID_C93,
 
     /* various PCM "codecs" */
     CODEC_ID_PCM_S16LE= 0x10000,
@@ -2251,6 +2252,7 @@ extern AVCodec asv1_decoder;
 extern AVCodec asv2_decoder;
 extern AVCodec avs_decoder;
 extern AVCodec bmp_decoder;
+extern AVCodec c93_decoder;
 extern AVCodec cavs_decoder;
 extern AVCodec cinepak_decoder;
 extern AVCodec cljr_decoder;

libavcodec/c93.c

@@ -0,0 +1,253 @@
+/*
+ * Interplay C93 video decoder
+ * Copyright (c) 2007 Anssi Hannula <anssi.hannula@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 "avcodec.h"
+#include "bytestream.h"
+
+typedef struct {
+    AVFrame pictures[2];
+    int currentpic;
+} C93DecoderContext;
+
+typedef enum {
+    C93_8X8_FROM_PREV  = 0x02,
+    C93_4X4_FROM_PREV  = 0x06,
+    C93_4X4_FROM_CURR  = 0x07,
+    C93_8X8_2COLOR     = 0x08,
+    C93_4X4_2COLOR     = 0x0A,
+    C93_4X4_4COLOR_GRP = 0x0B,
+    C93_4X4_4COLOR     = 0x0D,
+    C93_NOOP           = 0x0E,
+    C93_8X8_INTRA      = 0x0F,
+} C93BlockType;
+
+#define WIDTH   320
+#define HEIGHT  192
+
+#define C93_HAS_PALETTE 0x01
+#define C93_FIRST_FRAME 0x02
+
+static int c93_decode_init(AVCodecContext *avctx)
+{
+    avctx->pix_fmt = PIX_FMT_PAL8;
+    return 0;
+}
+
+static int c93_decode_end(AVCodecContext *avctx)
+{
+    C93DecoderContext * const c93 = avctx->priv_data;
+
+    if (c93->pictures[0].data[0])
+        avctx->release_buffer(avctx, &c93->pictures[0]);
+    if (c93->pictures[1].data[0])
+        avctx->release_buffer(avctx, &c93->pictures[1]);
+    return 0;
+}
+
+static inline int c93_copy_block(AVCodecContext *avctx, uint8_t *to,
+        uint8_t *from, int offset, int height, int stride)
+{
+    int i;
+    int width = height;
+    int from_x = offset % WIDTH;
+    int from_y = offset / WIDTH;
+    int overflow = from_x + width - WIDTH;
+
+    if (!from) {
+        /* silently ignoring predictive blocks in first frame */
+        return 0;
+    }
+
+    if (from_y + height > HEIGHT) {
+        av_log(avctx, AV_LOG_ERROR, "invalid offset %d during C93 decoding\n",
+               offset);
+        return -1;
+    }
+
+    if (overflow > 0) {
+        width -= overflow;
+        for (i = 0; i < height; i++) {
+            memcpy(&to[i*stride+width], &from[(from_y+i)*stride], overflow);
+        }
+    }
+
+    for (i = 0; i < height; i++) {
+        memcpy(&to[i*stride], &from[(from_y+i)*stride+from_x], width);
+    }
+
+    return 0;
+}
+
+static inline void c93_draw_n_color(uint8_t *out, int stride, int width,
+         int height, int bpp, uint8_t cols[4], uint8_t grps[4], uint32_t col)
+{
+    int x, y;
+    for (y = 0; y < height; y++) {
+        if (grps)
+            cols[0] = grps[3 * (y >> 1)];
+        for (x = 0; x < width; x++) {
+            if (grps)
+                cols[1]= grps[(x >> 1) + 1];
+            out[x + y*stride] = cols[col & ((1 << bpp) - 1)];
+            col >>= bpp;
+        }
+    }
+}
+
+static int c93_decode_frame(AVCodecContext *avctx, void *data,
+                            int *data_size, uint8_t * buf, int buf_size)
+{
+    C93DecoderContext * const c93 = avctx->priv_data;
+    AVFrame * const newpic = &c93->pictures[c93->currentpic];
+    AVFrame * const oldpic = &c93->pictures[c93->currentpic^1];
+    AVFrame *picture = data;
+    uint8_t *out;
+    int stride, i, x, y;
+    C93BlockType bt = 0;
+
+    c93->currentpic ^= 1;
+
+    newpic->reference = 1;
+    newpic->buffer_hints = FF_BUFFER_HINTS_VALID | FF_BUFFER_HINTS_PRESERVE |
+                         FF_BUFFER_HINTS_REUSABLE | FF_BUFFER_HINTS_READABLE;
+    if (avctx->reget_buffer(avctx, newpic)) {
+        av_log(avctx, AV_LOG_ERROR, "reget_buffer() failed\n");
+        return -1;
+    }
+
+    stride = newpic->linesize[0];
+
+    if (buf[0] & C93_FIRST_FRAME) {
+        newpic->pict_type = FF_I_TYPE;
+        newpic->key_frame = 1;
+    } else {
+        newpic->pict_type = FF_P_TYPE;
+        newpic->key_frame = 0;
+    }
+
+    if (*buf++ & C93_HAS_PALETTE) {
+        uint32_t *palette = (uint32_t *) newpic->data[1];
+        uint8_t *palbuf = buf + buf_size - 768 - 1;
+        for (i = 0; i < 256; i++) {
+            palette[i] = bytestream_get_be24(&palbuf);
+        }
+    } else {
+        if (oldpic->data[1])
+            memcpy(newpic->data[1], oldpic->data[1], 256 * 4);
+    }
+
+    for (y = 0; y < HEIGHT; y += 8) {
+        out = newpic->data[0] + y * stride;
+        for (x = 0; x < WIDTH; x += 8) {
+            uint8_t *copy_from = oldpic->data[0];
+            unsigned int offset, j;
+            uint8_t cols[4], grps[4];
+
+            if (!bt)
+                bt = *buf++;
+
+            switch (bt & 0x0F) {
+            case C93_8X8_FROM_PREV:
+                offset = bytestream_get_le16(&buf);
+                if (c93_copy_block(avctx, out, copy_from, offset, 8, stride))
+                    return -1;
+                break;
+
+            case C93_4X4_FROM_CURR:
+                copy_from = newpic->data[0];
+            case C93_4X4_FROM_PREV:
+                for (j = 0; j < 8; j += 4) {
+                    for (i = 0; i < 8; i += 4) {
+                        offset = bytestream_get_le16(&buf);
+                        if (c93_copy_block(avctx, &out[j*stride+i],
+                                           copy_from, offset, 4, stride))
+                            return -1;
+                    }
+                }
+                break;
+
+            case C93_8X8_2COLOR:
+                bytestream_get_buffer(&buf, cols, 2);
+                for (i = 0; i < 8; i++) {
+                    c93_draw_n_color(out + i*stride, stride, 8, 1, 1, cols,
+                                     NULL, *buf++);
+                }
+
+                break;
+
+            case C93_4X4_2COLOR:
+            case C93_4X4_4COLOR:
+            case C93_4X4_4COLOR_GRP:
+                for (j = 0; j < 8; j += 4) {
+                    for (i = 0; i < 8; i += 4) {
+                        if ((bt & 0x0F) == C93_4X4_2COLOR) {
+                            bytestream_get_buffer(&buf, cols, 2);
+                            c93_draw_n_color(out + i + j*stride, stride, 4, 4,
+                                    1, cols, NULL, bytestream_get_le16(&buf));
+                        } else if ((bt & 0x0F) == C93_4X4_4COLOR) {
+                            bytestream_get_buffer(&buf, cols, 4);
+                            c93_draw_n_color(out + i + j*stride, stride, 4, 4,
+                                    2, cols, NULL, bytestream_get_le32(&buf));
+                        } else {
+                            bytestream_get_buffer(&buf, grps, 4);
+                            c93_draw_n_color(out + i + j*stride, stride, 4, 4,
+                                    1, cols, grps, bytestream_get_le16(&buf));
+                        }
+                    }
+                }
+                break;
+
+            case C93_NOOP:
+                break;
+
+            case C93_8X8_INTRA:
+                for (j = 0; j < 8; j++)
+                    bytestream_get_buffer(&buf, out + j*stride, 8);
+                break;
+
+            default:
+                av_log(avctx, AV_LOG_ERROR, "unexpected type %x at %dx%d\n",
+                       bt & 0x0F, x, y);
+                return -1;
+            }
+            bt >>= 4;
+            out += 8;
+        }
+    }
+
+    *picture = *newpic;
+    *data_size = sizeof(AVFrame);
+
+    return buf_size;
+}
+
+AVCodec c93_decoder = {
+    "c93",
+    CODEC_TYPE_VIDEO,
+    CODEC_ID_C93,
+    sizeof(C93DecoderContext),
+    c93_decode_init,
+    NULL,
+    c93_decode_end,
+    c93_decode_frame,
+    CODEC_CAP_DR1,
+};

libavformat/Makefile

@@ -28,6 +28,7 @@ OBJS-$(CONFIG_AVI_DEMUXER)               += avidec.o riff.o
 OBJS-$(CONFIG_AVI_MUXER)                 += avienc.o riff.o
 OBJS-$(CONFIG_AVISYNTH)                  += avisynth.o
 OBJS-$(CONFIG_AVS_DEMUXER)               += avs.o vocdec.o voc.o riff.o
+OBJS-$(CONFIG_C93_DEMUXER)               += c93.o
 OBJS-$(CONFIG_CRC_MUXER)                 += crc.o
 OBJS-$(CONFIG_FRAMECRC_MUXER)            += crc.o
 OBJS-$(CONFIG_DAUD_DEMUXER)              += daud.o

libavformat/allformats.c

@@ -58,6 +58,7 @@ void av_register_all(void)
     av_register_input_format(&avisynth_demuxer);
 #endif
     REGISTER_DEMUXER (AVS, avs);
+    REGISTER_DEMUXER (C93, c93);
     REGISTER_MUXER   (CRC, crc);
     REGISTER_DEMUXER (DAUD, daud);
     REGISTER_DEMUXER (DC1394, dc1394);

libavformat/allformats.h

@@ -32,6 +32,7 @@ extern AVInputFormat audio_demuxer;
 extern AVInputFormat avi_demuxer;
 extern AVInputFormat avisynth_demuxer;
 extern AVInputFormat avs_demuxer;
+extern AVInputFormat c93_demuxer;
 extern AVInputFormat daud_demuxer;
 extern AVInputFormat dc1394_demuxer;
 extern AVInputFormat dsicin_demuxer;

libavformat/c93.c

@@ -0,0 +1,202 @@
+/*
+ * Interplay C93 demuxer
+ * Copyright (c) 2007 Anssi Hannula <anssi.hannula@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 "avformat.h"
+#include "voc.h"
+
+typedef struct {
+    uint16_t index;
+    uint8_t length;
+    uint8_t frames;
+} C93BlockRecord;
+
+typedef struct {
+    voc_dec_context_t voc;
+
+    C93BlockRecord block_records[512];
+    int current_block;
+
+    uint32_t frame_offsets[32];
+    int current_frame;
+    int next_pkt_is_audio;
+
+    AVStream *audio;
+} C93DemuxContext;
+
+static int c93_probe(AVProbeData *p)
+{
+    if (p->buf_size < 13)
+        return 0;
+
+    if (p->buf[0] == 0x01 && p->buf[1] == 0x00 &&
+        p->buf[4] == 0x01 + p->buf[2] &&
+        p->buf[8] == p->buf[4] + p->buf[6] &&
+        p->buf[12] == p->buf[8] + p->buf[10])
+        return AVPROBE_SCORE_MAX;
+
+    return 0;
+}
+
+static int c93_read_header(AVFormatContext *s,
+                           AVFormatParameters *ap)
+{
+    AVStream *video;
+    ByteIOContext *pb = &s->pb;
+    C93DemuxContext *c93 = s->priv_data;
+    int i;
+    int framecount = 0;
+
+    for (i = 0; i < 512; i++) {
+        c93->block_records[i].index = get_le16(pb);
+        c93->block_records[i].length = get_byte(pb);
+        c93->block_records[i].frames = get_byte(pb);
+        if (c93->block_records[i].frames > 32) {
+            av_log(s, AV_LOG_ERROR, "too many frames in block\n");
+            return AVERROR_INVALIDDATA;
+        }
+        framecount += c93->block_records[i].frames;
+    }
+
+    /* Audio streams are added if audio packets are found */
+    s->ctx_flags |= AVFMTCTX_NOHEADER;
+
+    video = av_new_stream(s, 0);
+    if (!video)
+        return AVERROR_NOMEM;
+
+    video->codec->codec_type = CODEC_TYPE_VIDEO;
+    video->codec->codec_id = CODEC_ID_C93;
+    video->codec->width = 320;
+    video->codec->height = 192;
+    /* 4:3 320x200 with 8 empty lines */
+    video->codec->sample_aspect_ratio = (AVRational) { 5, 6 };
+    video->time_base = (AVRational) { 2, 25 };
+    video->nb_frames = framecount;
+    video->duration = framecount;
+    video->start_time = 0;
+
+    c93->current_block = 0;
+    c93->current_frame = 0;
+    c93->next_pkt_is_audio = 0;
+    return 0;
+}
+
+#define C93_HAS_PALETTE 0x01
+#define C93_FIRST_FRAME 0x02
+
+static int c93_read_packet(AVFormatContext *s, AVPacket *pkt)
+{
+    ByteIOContext *pb = &s->pb;
+    C93DemuxContext *c93 = s->priv_data;
+    C93BlockRecord *br = &c93->block_records[c93->current_block];
+    int datasize;
+    int ret, i;
+
+    if (c93->next_pkt_is_audio) {
+        c93->current_frame++;
+        c93->next_pkt_is_audio = 0;
+        datasize = get_le16(pb);
+        if (datasize > 42) {
+            if (!c93->audio) {
+                c93->audio = av_new_stream(s, 1);
+                if (!c93->audio)
+                    return AVERROR_NOMEM;
+                c93->audio->codec->codec_type = CODEC_TYPE_AUDIO;
+            }
+            url_fskip(pb, 26); /* VOC header */
+            ret = voc_get_packet(s, pkt, c93->audio, datasize - 26);
+            if (ret > 0) {
+                pkt->stream_index = 1;
+                pkt->flags |= PKT_FLAG_KEY;
+                return ret;
+            }
+        }
+    }
+    if (c93->current_frame >= br->frames) {
+        if (c93->current_block >= 511 || !br[1].length)
+            return AVERROR_IO;
+        br++;
+        c93->current_block++;
+        c93->current_frame = 0;
+    }
+
+    if (c93->current_frame == 0) {
+        url_fseek(pb, br->index * 2048, SEEK_SET);
+        for (i = 0; i < 32; i++) {
+            c93->frame_offsets[i] = get_le32(pb);
+        }
+    }
+
+    url_fseek(pb,br->index * 2048 +
+            c93->frame_offsets[c93->current_frame], SEEK_SET);
+    datasize = get_le16(pb); /* video frame size */
+
+    ret = av_new_packet(pkt, datasize + 768 + 1);
+    if (ret < 0)
+        return ret;
+    pkt->data[0] = 0;
+    pkt->size = datasize + 1;
+
+    ret = get_buffer(pb, pkt->data + 1, datasize);
+    if (ret < datasize) {
+        ret = AVERROR_IO;
+        goto fail;
+    }
+
+    datasize = get_le16(pb); /* palette size */
+    if (datasize) {
+        if (datasize != 768) {
+            av_log(s, AV_LOG_ERROR, "invalid palette size %u\n", datasize);
+            ret = AVERROR_INVALIDDATA;
+            goto fail;
+        }
+        pkt->data[0] |= C93_HAS_PALETTE;
+        ret = get_buffer(pb, pkt->data + pkt->size, datasize);
+        if (ret < datasize) {
+            ret = AVERROR_IO;
+            goto fail;
+        }
+        pkt->size += 768;
+    }
+    pkt->stream_index = 0;
+    c93->next_pkt_is_audio = 1;
+
+    /* only the first frame is guaranteed to not reference previous frames */
+    if (c93->current_block == 0 && c93->current_frame == 0) {
+        pkt->flags |= PKT_FLAG_KEY;
+        pkt->data[0] |= C93_FIRST_FRAME;
+    }
+    return 0;
+
+    fail:
+    av_free_packet(pkt);
+    return ret;
+}
+
+AVInputFormat c93_demuxer = {
+    "c93",
+    "Interplay C93",
+    sizeof(C93DemuxContext),
+    c93_probe,
+    c93_read_header,
+    c93_read_packet,
+};