/* * Sierra VMD Audio & Video Decoders * Copyright (C) 2004 the ffmpeg project * * 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 vmdvideo.c * Sierra VMD audio & video decoders * by Vladimir "VAG" Gneushev (vagsoft at mail.ru) * for more information on the Sierra VMD format, visit: * http://www.pcisys.net/~melanson/codecs/ * * The video decoder outputs PAL8 colorspace data. The decoder expects * a 0x330-byte VMD file header to be transmitted via extradata during * codec initialization. Each encoded frame that is sent to this decoder * is expected to be prepended with the appropriate 16-byte frame * information record from the VMD file. * * The audio decoder, like the video decoder, expects each encoded data * chunk to be prepended with the appropriate 16-byte frame information * record from the VMD file. It does not require the 0x330-byte VMD file * header, but it does need the audio setup parameters passed in through * normal libavcodec API means. */ #include <stdio.h> #include <stdlib.h> #include <string.h> #include <unistd.h> #include "avcodec.h" #include "dsputil.h" #define VMD_HEADER_SIZE 0x330 #define PALETTE_COUNT 256 /* * Video Decoder */ typedef struct VmdVideoContext { AVCodecContext *avctx; DSPContext dsp; AVFrame frame; AVFrame prev_frame; const unsigned char *buf; int size; unsigned char palette[PALETTE_COUNT * 4]; unsigned char *unpack_buffer; int unpack_buffer_size; int x_off, y_off; } VmdVideoContext; #define QUEUE_SIZE 0x1000 #define QUEUE_MASK 0x0FFF static void lz_unpack(const unsigned char *src, unsigned char *dest, int dest_len) { const unsigned char *s; unsigned char *d; unsigned char *d_end; unsigned char queue[QUEUE_SIZE]; unsigned int qpos; unsigned int dataleft; unsigned int chainofs; unsigned int chainlen; unsigned int speclen; unsigned char tag; unsigned int i, j; s = src; d = dest; d_end = d + dest_len; dataleft = AV_RL32(s); s += 4; memset(queue, 0x20, QUEUE_SIZE); if (AV_RL32(s) == 0x56781234) { s += 4; qpos = 0x111; speclen = 0xF + 3; } else { qpos = 0xFEE; speclen = 100; /* no speclen */ } while (dataleft > 0) { tag = *s++; if ((tag == 0xFF) && (dataleft > 8)) { if (d + 8 > d_end) return; for (i = 0; i < 8; i++) { queue[qpos++] = *d++ = *s++; qpos &= QUEUE_MASK; } dataleft -= 8; } else { for (i = 0; i < 8; i++) { if (dataleft == 0) break; if (tag & 0x01) { if (d + 1 > d_end) return; queue[qpos++] = *d++ = *s++; qpos &= QUEUE_MASK; dataleft--; } else { chainofs = *s++; chainofs |= ((*s & 0xF0) << 4); chainlen = (*s++ & 0x0F) + 3; if (chainlen == speclen) chainlen = *s++ + 0xF + 3; if (d + chainlen > d_end) return; for (j = 0; j < chainlen; j++) { *d = queue[chainofs++ & QUEUE_MASK]; queue[qpos++] = *d++; qpos &= QUEUE_MASK; } dataleft -= chainlen; } tag >>= 1; } } } } static int rle_unpack(const unsigned char *src, unsigned char *dest, int src_len, int dest_len) { const unsigned char *ps; unsigned char *pd; int i, l; unsigned char *dest_end = dest + dest_len; ps = src; pd = dest; if (src_len & 1) *pd++ = *ps++; src_len >>= 1; i = 0; do { l = *ps++; if (l & 0x80) { l = (l & 0x7F) * 2; if (pd + l > dest_end) return (ps - src); memcpy(pd, ps, l); ps += l; pd += l; } else { if (pd + i > dest_end) return (ps - src); for (i = 0; i < l; i++) { *pd++ = ps[0]; *pd++ = ps[1]; } ps += 2; } i += l; } while (i < src_len); return (ps - src); } static void vmd_decode(VmdVideoContext *s) { int i; unsigned int *palette32; unsigned char r, g, b; /* point to the start of the encoded data */ const unsigned char *p = s->buf + 16; const unsigned char *pb; unsigned char meth; unsigned char *dp; /* pointer to current frame */ unsigned char *pp; /* pointer to previous frame */ unsigned char len; int ofs; int frame_x, frame_y; int frame_width, frame_height; int dp_size; frame_x = AV_RL16(&s->buf[6]); frame_y = AV_RL16(&s->buf[8]); frame_width = AV_RL16(&s->buf[10]) - frame_x + 1; frame_height = AV_RL16(&s->buf[12]) - frame_y + 1; if ((frame_width == s->avctx->width && frame_height == s->avctx->height) && (frame_x || frame_y)) { s->x_off = frame_x; s->y_off = frame_y; } frame_x -= s->x_off; frame_y -= s->y_off; /* if only a certain region will be updated, copy the entire previous * frame before the decode */ if (frame_x || frame_y || (frame_width != s->avctx->width) || (frame_height != s->avctx->height)) { memcpy(s->frame.data[0], s->prev_frame.data[0], s->avctx->height * s->frame.linesize[0]); } /* check if there is a new palette */ if (s->buf[15] & 0x02) { p += 2; palette32 = (unsigned int *)s->palette; for (i = 0; i < PALETTE_COUNT; i++) { r = *p++ * 4; g = *p++ * 4; b = *p++ * 4; palette32[i] = (r << 16) | (g << 8) | (b); } s->size -= (256 * 3 + 2); } if (s->size >= 0) { /* originally UnpackFrame in VAG's code */ pb = p; meth = *pb++; if (meth & 0x80) { lz_unpack(pb, s->unpack_buffer, s->unpack_buffer_size); meth &= 0x7F; pb = s->unpack_buffer; } dp = &s->frame.data[0][frame_y * s->frame.linesize[0] + frame_x]; dp_size = s->frame.linesize[0] * s->avctx->height; pp = &s->prev_frame.data[0][frame_y * s->prev_frame.linesize[0] + frame_x]; switch (meth) { case 1: for (i = 0; i < frame_height; i++) { ofs = 0; do { len = *pb++; if (len & 0x80) { len = (len & 0x7F) + 1; if (ofs + len > frame_width) return; memcpy(&dp[ofs], pb, len); pb += len; ofs += len; } else { /* interframe pixel copy */ if (ofs + len + 1 > frame_width) return; memcpy(&dp[ofs], &pp[ofs], len + 1); ofs += len + 1; } } while (ofs < frame_width); if (ofs > frame_width) { av_log(s->avctx, AV_LOG_ERROR, "VMD video: offset > width (%d > %d)\n", ofs, frame_width); break; } dp += s->frame.linesize[0]; pp += s->prev_frame.linesize[0]; } break; case 2: for (i = 0; i < frame_height; i++) { memcpy(dp, pb, frame_width); pb += frame_width; dp += s->frame.linesize[0]; pp += s->prev_frame.linesize[0]; } break; case 3: for (i = 0; i < frame_height; i++) { ofs = 0; do { len = *pb++; if (len & 0x80) { len = (len & 0x7F) + 1; if (*pb++ == 0xFF) len = rle_unpack(pb, &dp[ofs], len, frame_width - ofs); else memcpy(&dp[ofs], pb, len); pb += len; ofs += len; } else { /* interframe pixel copy */ if (ofs + len + 1 > frame_width) return; memcpy(&dp[ofs], &pp[ofs], len + 1); ofs += len + 1; } } while (ofs < frame_width); if (ofs > frame_width) { av_log(s->avctx, AV_LOG_ERROR, "VMD video: offset > width (%d > %d)\n", ofs, frame_width); } dp += s->frame.linesize[0]; pp += s->prev_frame.linesize[0]; } break; } } } static int vmdvideo_decode_init(AVCodecContext *avctx) { VmdVideoContext *s = avctx->priv_data; int i; unsigned int *palette32; int palette_index = 0; unsigned char r, g, b; unsigned char *vmd_header; unsigned char *raw_palette; s->avctx = avctx; avctx->pix_fmt = PIX_FMT_PAL8; dsputil_init(&s->dsp, avctx); /* make sure the VMD header made it */ if (s->avctx->extradata_size != VMD_HEADER_SIZE) { av_log(s->avctx, AV_LOG_ERROR, "VMD video: expected extradata size of %d\n", VMD_HEADER_SIZE); return -1; } vmd_header = (unsigned char *)avctx->extradata; s->unpack_buffer_size = AV_RL32(&vmd_header[800]); s->unpack_buffer = av_malloc(s->unpack_buffer_size); if (!s->unpack_buffer) return -1; /* load up the initial palette */ raw_palette = &vmd_header[28]; palette32 = (unsigned int *)s->palette; for (i = 0; i < PALETTE_COUNT; i++) { r = raw_palette[palette_index++] * 4; g = raw_palette[palette_index++] * 4; b = raw_palette[palette_index++] * 4; palette32[i] = (r << 16) | (g << 8) | (b); } s->frame.data[0] = s->prev_frame.data[0] = NULL; return 0; } static int vmdvideo_decode_frame(AVCodecContext *avctx, void *data, int *data_size, const uint8_t *buf, int buf_size) { VmdVideoContext *s = avctx->priv_data; s->buf = buf; s->size = buf_size; if (buf_size < 16) return buf_size; s->frame.reference = 1; if (avctx->get_buffer(avctx, &s->frame)) { av_log(s->avctx, AV_LOG_ERROR, "VMD Video: get_buffer() failed\n"); return -1; } vmd_decode(s); /* make the palette available on the way out */ memcpy(s->frame.data[1], s->palette, PALETTE_COUNT * 4); /* shuffle frames */ FFSWAP(AVFrame, s->frame, s->prev_frame); if (s->frame.data[0]) avctx->release_buffer(avctx, &s->frame); *data_size = sizeof(AVFrame); *(AVFrame*)data = s->prev_frame; /* report that the buffer was completely consumed */ return buf_size; } static int vmdvideo_decode_end(AVCodecContext *avctx) { VmdVideoContext *s = avctx->priv_data; if (s->prev_frame.data[0]) avctx->release_buffer(avctx, &s->prev_frame); av_free(s->unpack_buffer); return 0; } /* * Audio Decoder */ typedef struct VmdAudioContext { AVCodecContext *avctx; int channels; int bits; int block_align; int predictors[2]; } VmdAudioContext; static uint16_t vmdaudio_table[128] = { 0x000, 0x008, 0x010, 0x020, 0x030, 0x040, 0x050, 0x060, 0x070, 0x080, 0x090, 0x0A0, 0x0B0, 0x0C0, 0x0D0, 0x0E0, 0x0F0, 0x100, 0x110, 0x120, 0x130, 0x140, 0x150, 0x160, 0x170, 0x180, 0x190, 0x1A0, 0x1B0, 0x1C0, 0x1D0, 0x1E0, 0x1F0, 0x200, 0x208, 0x210, 0x218, 0x220, 0x228, 0x230, 0x238, 0x240, 0x248, 0x250, 0x258, 0x260, 0x268, 0x270, 0x278, 0x280, 0x288, 0x290, 0x298, 0x2A0, 0x2A8, 0x2B0, 0x2B8, 0x2C0, 0x2C8, 0x2D0, 0x2D8, 0x2E0, 0x2E8, 0x2F0, 0x2F8, 0x300, 0x308, 0x310, 0x318, 0x320, 0x328, 0x330, 0x338, 0x340, 0x348, 0x350, 0x358, 0x360, 0x368, 0x370, 0x378, 0x380, 0x388, 0x390, 0x398, 0x3A0, 0x3A8, 0x3B0, 0x3B8, 0x3C0, 0x3C8, 0x3D0, 0x3D8, 0x3E0, 0x3E8, 0x3F0, 0x3F8, 0x400, 0x440, 0x480, 0x4C0, 0x500, 0x540, 0x580, 0x5C0, 0x600, 0x640, 0x680, 0x6C0, 0x700, 0x740, 0x780, 0x7C0, 0x800, 0x900, 0xA00, 0xB00, 0xC00, 0xD00, 0xE00, 0xF00, 0x1000, 0x1400, 0x1800, 0x1C00, 0x2000, 0x3000, 0x4000 }; static int vmdaudio_decode_init(AVCodecContext *avctx) { VmdAudioContext *s = avctx->priv_data; s->avctx = avctx; s->channels = avctx->channels; s->bits = avctx->bits_per_sample; s->block_align = avctx->block_align; av_log(s->avctx, AV_LOG_DEBUG, "%d channels, %d bits/sample, block align = %d, sample rate = %d\n", s->channels, s->bits, s->block_align, avctx->sample_rate); return 0; } static void vmdaudio_decode_audio(VmdAudioContext *s, unsigned char *data, const uint8_t *buf, int stereo) { int i; int chan = 0; int16_t *out = (int16_t*)data; for(i = 0; i < s->block_align; i++) { if(buf[i] & 0x80) s->predictors[chan] -= vmdaudio_table[buf[i] & 0x7F]; else s->predictors[chan] += vmdaudio_table[buf[i]]; s->predictors[chan] = av_clip_int16(s->predictors[chan]); out[i] = s->predictors[chan]; chan ^= stereo; } } static int vmdaudio_loadsound(VmdAudioContext *s, unsigned char *data, const uint8_t *buf, int silence) { int bytes_decoded = 0; int i; // if (silence) // av_log(s->avctx, AV_LOG_INFO, "silent block!\n"); if (s->channels == 2) { /* stereo handling */ if (silence) { memset(data, 0, s->block_align * 2); } else { if (s->bits == 16) vmdaudio_decode_audio(s, data, buf, 1); else { /* copy the data but convert it to signed */ for (i = 0; i < s->block_align; i++){ *data++ = buf[i] + 0x80; *data++ = buf[i] + 0x80; } } } } else { bytes_decoded = s->block_align * 2; /* mono handling */ if (silence) { memset(data, 0, s->block_align * 2); } else { if (s->bits == 16) { vmdaudio_decode_audio(s, data, buf, 0); } else { /* copy the data but convert it to signed */ for (i = 0; i < s->block_align; i++){ *data++ = buf[i] + 0x80; *data++ = buf[i] + 0x80; } } } } return s->block_align * 2; } static int vmdaudio_decode_frame(AVCodecContext *avctx, void *data, int *data_size, const uint8_t *buf, int buf_size) { VmdAudioContext *s = avctx->priv_data; unsigned char *output_samples = (unsigned char *)data; /* point to the start of the encoded data */ const unsigned char *p = buf + 16; if (buf_size < 16) return buf_size; if (buf[6] == 1) { /* the chunk contains audio */ *data_size = vmdaudio_loadsound(s, output_samples, p, 0); } else if (buf[6] == 2) { /* the chunk may contain audio */ p += 4; *data_size = vmdaudio_loadsound(s, output_samples, p, (buf_size == 16)); output_samples += (s->block_align * s->bits / 8); } else if (buf[6] == 3) { /* silent chunk */ *data_size = vmdaudio_loadsound(s, output_samples, p, 1); } return buf_size; } /* * Public Data Structures */ AVCodec vmdvideo_decoder = { "vmdvideo", CODEC_TYPE_VIDEO, CODEC_ID_VMDVIDEO, sizeof(VmdVideoContext), vmdvideo_decode_init, NULL, vmdvideo_decode_end, vmdvideo_decode_frame, CODEC_CAP_DR1, }; AVCodec vmdaudio_decoder = { "vmdaudio", CODEC_TYPE_AUDIO, CODEC_ID_VMDAUDIO, sizeof(VmdAudioContext), vmdaudio_decode_init, NULL, NULL, vmdaudio_decode_frame, };