| /* |
| * Westwood Studios VQA Video Decoder |
| * Copyright (C) 2003 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 libavcodec/vqavideo.c |
| * VQA Video Decoder by Mike Melanson (melanson@pcisys.net) |
| * For more information about the VQA format, visit: |
| * http://wiki.multimedia.cx/index.php?title=VQA |
| * |
| * The VQA video decoder outputs PAL8 or RGB555 colorspace data, depending |
| * on the type of data in the file. |
| * |
| * This decoder needs the 42-byte VQHD header from the beginning |
| * of the VQA file passed through the extradata field. The VQHD header |
| * is laid out as: |
| * |
| * bytes 0-3 chunk fourcc: 'VQHD' |
| * bytes 4-7 chunk size in big-endian format, should be 0x0000002A |
| * bytes 8-49 VQHD chunk data |
| * |
| * Bytes 8-49 are what this decoder expects to see. |
| * |
| * Briefly, VQA is a vector quantized animation format that operates in a |
| * VGA palettized colorspace. It operates on pixel vectors (blocks) |
| * of either 4x2 or 4x4 in size. Compressed VQA chunks can contain vector |
| * codebooks, palette information, and code maps for rendering vectors onto |
| * frames. Any of these components can also be compressed with a run-length |
| * encoding (RLE) algorithm commonly referred to as "format80". |
| * |
| * VQA takes a novel approach to rate control. Each group of n frames |
| * (usually, n = 8) relies on a different vector codebook. Rather than |
| * transporting an entire codebook every 8th frame, the new codebook is |
| * broken up into 8 pieces and sent along with the compressed video chunks |
| * for each of the 8 frames preceding the 8 frames which require the |
| * codebook. A full codebook is also sent on the very first frame of a |
| * file. This is an interesting technique, although it makes random file |
| * seeking difficult despite the fact that the frames are all intracoded. |
| * |
| * V1,2 VQA uses 12-bit codebook indexes. If the 12-bit indexes were |
| * packed into bytes and then RLE compressed, bytewise, the results would |
| * be poor. That is why the coding method divides each index into 2 parts, |
| * the top 4 bits and the bottom 8 bits, then RL encodes the 4-bit pieces |
| * together and the 8-bit pieces together. If most of the vectors are |
| * clustered into one group of 256 vectors, most of the 4-bit index pieces |
| * should be the same. |
| */ |
| |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <unistd.h> |
| |
| #include "libavutil/intreadwrite.h" |
| #include "avcodec.h" |
| |
| #define PALETTE_COUNT 256 |
| #define VQA_HEADER_SIZE 0x2A |
| #define CHUNK_PREAMBLE_SIZE 8 |
| |
| /* allocate the maximum vector space, regardless of the file version: |
| * (0xFF00 codebook vectors + 0x100 solid pixel vectors) * (4x4 pixels/block) */ |
| #define MAX_CODEBOOK_VECTORS 0xFF00 |
| #define SOLID_PIXEL_VECTORS 0x100 |
| #define MAX_VECTORS (MAX_CODEBOOK_VECTORS + SOLID_PIXEL_VECTORS) |
| #define MAX_CODEBOOK_SIZE (MAX_VECTORS * 4 * 4) |
| |
| #define CBF0_TAG MKBETAG('C', 'B', 'F', '0') |
| #define CBFZ_TAG MKBETAG('C', 'B', 'F', 'Z') |
| #define CBP0_TAG MKBETAG('C', 'B', 'P', '0') |
| #define CBPZ_TAG MKBETAG('C', 'B', 'P', 'Z') |
| #define CPL0_TAG MKBETAG('C', 'P', 'L', '0') |
| #define CPLZ_TAG MKBETAG('C', 'P', 'L', 'Z') |
| #define VPTZ_TAG MKBETAG('V', 'P', 'T', 'Z') |
| |
| #define VQA_DEBUG 0 |
| |
| #if VQA_DEBUG |
| #define vqa_debug printf |
| #else |
| static inline void vqa_debug(const char *format, ...) { } |
| #endif |
| |
| typedef struct VqaContext { |
| |
| AVCodecContext *avctx; |
| AVFrame frame; |
| |
| const unsigned char *buf; |
| int size; |
| |
| uint32_t palette[PALETTE_COUNT]; |
| |
| int width; /* width of a frame */ |
| int height; /* height of a frame */ |
| int vector_width; /* width of individual vector */ |
| int vector_height; /* height of individual vector */ |
| int vqa_version; /* this should be either 1, 2 or 3 */ |
| |
| unsigned char *codebook; /* the current codebook */ |
| int codebook_size; |
| unsigned char *next_codebook_buffer; /* accumulator for next codebook */ |
| int next_codebook_buffer_index; |
| |
| unsigned char *decode_buffer; |
| int decode_buffer_size; |
| |
| /* number of frames to go before replacing codebook */ |
| int partial_countdown; |
| int partial_count; |
| |
| } VqaContext; |
| |
| static av_cold int vqa_decode_init(AVCodecContext *avctx) |
| { |
| VqaContext *s = avctx->priv_data; |
| unsigned char *vqa_header; |
| int i, j, codebook_index; |
| |
| s->avctx = avctx; |
| avctx->pix_fmt = PIX_FMT_PAL8; |
| |
| /* make sure the extradata made it */ |
| if (s->avctx->extradata_size != VQA_HEADER_SIZE) { |
| av_log(s->avctx, AV_LOG_ERROR, " VQA video: expected extradata size of %d\n", VQA_HEADER_SIZE); |
| return -1; |
| } |
| |
| /* load up the VQA parameters from the header */ |
| vqa_header = (unsigned char *)s->avctx->extradata; |
| s->vqa_version = vqa_header[0]; |
| s->width = AV_RL16(&vqa_header[6]); |
| s->height = AV_RL16(&vqa_header[8]); |
| if(avcodec_check_dimensions(avctx, s->width, s->height)){ |
| s->width= s->height= 0; |
| return -1; |
| } |
| s->vector_width = vqa_header[10]; |
| s->vector_height = vqa_header[11]; |
| s->partial_count = s->partial_countdown = vqa_header[13]; |
| |
| /* the vector dimensions have to meet very stringent requirements */ |
| if ((s->vector_width != 4) || |
| ((s->vector_height != 2) && (s->vector_height != 4))) { |
| /* return without further initialization */ |
| return -1; |
| } |
| |
| if (s->width & (s->vector_width - 1) || |
| s->height & (s->vector_height - 1)) { |
| av_log(avctx, AV_LOG_ERROR, "Image size not multiple of block size\n"); |
| return AVERROR_INVALIDDATA; |
| } |
| |
| /* allocate codebooks */ |
| s->codebook_size = MAX_CODEBOOK_SIZE; |
| s->codebook = av_malloc(s->codebook_size); |
| s->next_codebook_buffer = av_malloc(s->codebook_size); |
| |
| /* initialize the solid-color vectors */ |
| if (s->vector_height == 4) { |
| codebook_index = 0xFF00 * 16; |
| for (i = 0; i < 256; i++) |
| for (j = 0; j < 16; j++) |
| s->codebook[codebook_index++] = i; |
| } else { |
| codebook_index = 0xF00 * 8; |
| for (i = 0; i < 256; i++) |
| for (j = 0; j < 8; j++) |
| s->codebook[codebook_index++] = i; |
| } |
| s->next_codebook_buffer_index = 0; |
| |
| /* allocate decode buffer */ |
| s->decode_buffer_size = (s->width / s->vector_width) * |
| (s->height / s->vector_height) * 2; |
| s->decode_buffer = av_malloc(s->decode_buffer_size); |
| |
| s->frame.data[0] = NULL; |
| |
| return 0; |
| } |
| |
| #define CHECK_COUNT() \ |
| if (dest_index + count > dest_size) { \ |
| av_log(NULL, AV_LOG_ERROR, " VQA video: decode_format80 problem: next op would overflow dest_index\n"); \ |
| av_log(NULL, AV_LOG_ERROR, " VQA video: current dest_index = %d, count = %d, dest_size = %d\n", \ |
| dest_index, count, dest_size); \ |
| return; \ |
| } |
| |
| static void decode_format80(const unsigned char *src, int src_size, |
| unsigned char *dest, int dest_size, int check_size) { |
| |
| int src_index = 0; |
| int dest_index = 0; |
| int count; |
| int src_pos; |
| unsigned char color; |
| int i; |
| |
| while (src_index < src_size) { |
| |
| vqa_debug(" opcode %02X: ", src[src_index]); |
| |
| /* 0x80 means that frame is finished */ |
| if (src[src_index] == 0x80) |
| return; |
| |
| if (dest_index >= dest_size) { |
| av_log(NULL, AV_LOG_ERROR, " VQA video: decode_format80 problem: dest_index (%d) exceeded dest_size (%d)\n", |
| dest_index, dest_size); |
| return; |
| } |
| |
| if (src[src_index] == 0xFF) { |
| |
| src_index++; |
| count = AV_RL16(&src[src_index]); |
| src_index += 2; |
| src_pos = AV_RL16(&src[src_index]); |
| src_index += 2; |
| vqa_debug("(1) copy %X bytes from absolute pos %X\n", count, src_pos); |
| CHECK_COUNT(); |
| for (i = 0; i < count; i++) |
| dest[dest_index + i] = dest[src_pos + i]; |
| dest_index += count; |
| |
| } else if (src[src_index] == 0xFE) { |
| |
| src_index++; |
| count = AV_RL16(&src[src_index]); |
| src_index += 2; |
| color = src[src_index++]; |
| vqa_debug("(2) set %X bytes to %02X\n", count, color); |
| CHECK_COUNT(); |
| memset(&dest[dest_index], color, count); |
| dest_index += count; |
| |
| } else if ((src[src_index] & 0xC0) == 0xC0) { |
| |
| count = (src[src_index++] & 0x3F) + 3; |
| src_pos = AV_RL16(&src[src_index]); |
| src_index += 2; |
| vqa_debug("(3) copy %X bytes from absolute pos %X\n", count, src_pos); |
| CHECK_COUNT(); |
| for (i = 0; i < count; i++) |
| dest[dest_index + i] = dest[src_pos + i]; |
| dest_index += count; |
| |
| } else if (src[src_index] > 0x80) { |
| |
| count = src[src_index++] & 0x3F; |
| vqa_debug("(4) copy %X bytes from source to dest\n", count); |
| CHECK_COUNT(); |
| memcpy(&dest[dest_index], &src[src_index], count); |
| src_index += count; |
| dest_index += count; |
| |
| } else { |
| |
| count = ((src[src_index] & 0x70) >> 4) + 3; |
| src_pos = AV_RB16(&src[src_index]) & 0x0FFF; |
| src_index += 2; |
| vqa_debug("(5) copy %X bytes from relpos %X\n", count, src_pos); |
| CHECK_COUNT(); |
| for (i = 0; i < count; i++) |
| dest[dest_index + i] = dest[dest_index - src_pos + i]; |
| dest_index += count; |
| } |
| } |
| |
| /* validate that the entire destination buffer was filled; this is |
| * important for decoding frame maps since each vector needs to have a |
| * codebook entry; it is not important for compressed codebooks because |
| * not every entry needs to be filled */ |
| if (check_size) |
| if (dest_index < dest_size) |
| av_log(NULL, AV_LOG_ERROR, " VQA video: decode_format80 problem: decode finished with dest_index (%d) < dest_size (%d)\n", |
| dest_index, dest_size); |
| } |
| |
| static void vqa_decode_chunk(VqaContext *s) |
| { |
| unsigned int chunk_type; |
| unsigned int chunk_size; |
| int byte_skip; |
| unsigned int index = 0; |
| int i; |
| unsigned char r, g, b; |
| int index_shift; |
| |
| int cbf0_chunk = -1; |
| int cbfz_chunk = -1; |
| int cbp0_chunk = -1; |
| int cbpz_chunk = -1; |
| int cpl0_chunk = -1; |
| int cplz_chunk = -1; |
| int vptz_chunk = -1; |
| |
| int x, y; |
| int lines = 0; |
| int pixel_ptr; |
| int vector_index = 0; |
| int lobyte = 0; |
| int hibyte = 0; |
| int lobytes = 0; |
| int hibytes = s->decode_buffer_size / 2; |
| |
| /* first, traverse through the frame and find the subchunks */ |
| while (index < s->size) { |
| |
| chunk_type = AV_RB32(&s->buf[index]); |
| chunk_size = AV_RB32(&s->buf[index + 4]); |
| |
| switch (chunk_type) { |
| |
| case CBF0_TAG: |
| cbf0_chunk = index; |
| break; |
| |
| case CBFZ_TAG: |
| cbfz_chunk = index; |
| break; |
| |
| case CBP0_TAG: |
| cbp0_chunk = index; |
| break; |
| |
| case CBPZ_TAG: |
| cbpz_chunk = index; |
| break; |
| |
| case CPL0_TAG: |
| cpl0_chunk = index; |
| break; |
| |
| case CPLZ_TAG: |
| cplz_chunk = index; |
| break; |
| |
| case VPTZ_TAG: |
| vptz_chunk = index; |
| break; |
| |
| default: |
| av_log(s->avctx, AV_LOG_ERROR, " VQA video: Found unknown chunk type: %c%c%c%c (%08X)\n", |
| (chunk_type >> 24) & 0xFF, |
| (chunk_type >> 16) & 0xFF, |
| (chunk_type >> 8) & 0xFF, |
| (chunk_type >> 0) & 0xFF, |
| chunk_type); |
| break; |
| } |
| |
| byte_skip = chunk_size & 0x01; |
| index += (CHUNK_PREAMBLE_SIZE + chunk_size + byte_skip); |
| } |
| |
| /* next, deal with the palette */ |
| if ((cpl0_chunk != -1) && (cplz_chunk != -1)) { |
| |
| /* a chunk should not have both chunk types */ |
| av_log(s->avctx, AV_LOG_ERROR, " VQA video: problem: found both CPL0 and CPLZ chunks\n"); |
| return; |
| } |
| |
| /* decompress the palette chunk */ |
| if (cplz_chunk != -1) { |
| |
| /* yet to be handled */ |
| |
| } |
| |
| /* convert the RGB palette into the machine's endian format */ |
| if (cpl0_chunk != -1) { |
| |
| chunk_size = AV_RB32(&s->buf[cpl0_chunk + 4]); |
| /* sanity check the palette size */ |
| if (chunk_size / 3 > 256) { |
| av_log(s->avctx, AV_LOG_ERROR, " VQA video: problem: found a palette chunk with %d colors\n", |
| chunk_size / 3); |
| return; |
| } |
| cpl0_chunk += CHUNK_PREAMBLE_SIZE; |
| for (i = 0; i < chunk_size / 3; i++) { |
| /* scale by 4 to transform 6-bit palette -> 8-bit */ |
| r = s->buf[cpl0_chunk++] * 4; |
| g = s->buf[cpl0_chunk++] * 4; |
| b = s->buf[cpl0_chunk++] * 4; |
| s->palette[i] = (r << 16) | (g << 8) | (b); |
| } |
| } |
| |
| /* next, look for a full codebook */ |
| if ((cbf0_chunk != -1) && (cbfz_chunk != -1)) { |
| |
| /* a chunk should not have both chunk types */ |
| av_log(s->avctx, AV_LOG_ERROR, " VQA video: problem: found both CBF0 and CBFZ chunks\n"); |
| return; |
| } |
| |
| /* decompress the full codebook chunk */ |
| if (cbfz_chunk != -1) { |
| |
| chunk_size = AV_RB32(&s->buf[cbfz_chunk + 4]); |
| cbfz_chunk += CHUNK_PREAMBLE_SIZE; |
| decode_format80(&s->buf[cbfz_chunk], chunk_size, |
| s->codebook, s->codebook_size, 0); |
| } |
| |
| /* copy a full codebook */ |
| if (cbf0_chunk != -1) { |
| |
| chunk_size = AV_RB32(&s->buf[cbf0_chunk + 4]); |
| /* sanity check the full codebook size */ |
| if (chunk_size > MAX_CODEBOOK_SIZE) { |
| av_log(s->avctx, AV_LOG_ERROR, " VQA video: problem: CBF0 chunk too large (0x%X bytes)\n", |
| chunk_size); |
| return; |
| } |
| cbf0_chunk += CHUNK_PREAMBLE_SIZE; |
| |
| memcpy(s->codebook, &s->buf[cbf0_chunk], chunk_size); |
| } |
| |
| /* decode the frame */ |
| if (vptz_chunk == -1) { |
| |
| /* something is wrong if there is no VPTZ chunk */ |
| av_log(s->avctx, AV_LOG_ERROR, " VQA video: problem: no VPTZ chunk found\n"); |
| return; |
| } |
| |
| chunk_size = AV_RB32(&s->buf[vptz_chunk + 4]); |
| vptz_chunk += CHUNK_PREAMBLE_SIZE; |
| decode_format80(&s->buf[vptz_chunk], chunk_size, |
| s->decode_buffer, s->decode_buffer_size, 1); |
| |
| /* render the final PAL8 frame */ |
| if (s->vector_height == 4) |
| index_shift = 4; |
| else |
| index_shift = 3; |
| for (y = 0; y < s->frame.linesize[0] * s->height; |
| y += s->frame.linesize[0] * s->vector_height) { |
| |
| for (x = y; x < y + s->width; x += 4, lobytes++, hibytes++) { |
| pixel_ptr = x; |
| |
| /* get the vector index, the method for which varies according to |
| * VQA file version */ |
| switch (s->vqa_version) { |
| |
| case 1: |
| /* still need sample media for this case (only one game, "Legend of |
| * Kyrandia III : Malcolm's Revenge", is known to use this version) */ |
| lobyte = s->decode_buffer[lobytes * 2]; |
| hibyte = s->decode_buffer[(lobytes * 2) + 1]; |
| vector_index = ((hibyte << 8) | lobyte) >> 3; |
| vector_index <<= index_shift; |
| lines = s->vector_height; |
| /* uniform color fill - a quick hack */ |
| if (hibyte == 0xFF) { |
| while (lines--) { |
| s->frame.data[0][pixel_ptr + 0] = 255 - lobyte; |
| s->frame.data[0][pixel_ptr + 1] = 255 - lobyte; |
| s->frame.data[0][pixel_ptr + 2] = 255 - lobyte; |
| s->frame.data[0][pixel_ptr + 3] = 255 - lobyte; |
| pixel_ptr += s->frame.linesize[0]; |
| } |
| lines=0; |
| } |
| break; |
| |
| case 2: |
| lobyte = s->decode_buffer[lobytes]; |
| hibyte = s->decode_buffer[hibytes]; |
| vector_index = (hibyte << 8) | lobyte; |
| vector_index <<= index_shift; |
| lines = s->vector_height; |
| break; |
| |
| case 3: |
| /* not implemented yet */ |
| lines = 0; |
| break; |
| } |
| |
| while (lines--) { |
| s->frame.data[0][pixel_ptr + 0] = s->codebook[vector_index++]; |
| s->frame.data[0][pixel_ptr + 1] = s->codebook[vector_index++]; |
| s->frame.data[0][pixel_ptr + 2] = s->codebook[vector_index++]; |
| s->frame.data[0][pixel_ptr + 3] = s->codebook[vector_index++]; |
| pixel_ptr += s->frame.linesize[0]; |
| } |
| } |
| } |
| |
| /* handle partial codebook */ |
| if ((cbp0_chunk != -1) && (cbpz_chunk != -1)) { |
| /* a chunk should not have both chunk types */ |
| av_log(s->avctx, AV_LOG_ERROR, " VQA video: problem: found both CBP0 and CBPZ chunks\n"); |
| return; |
| } |
| |
| if (cbp0_chunk != -1) { |
| |
| chunk_size = AV_RB32(&s->buf[cbp0_chunk + 4]); |
| cbp0_chunk += CHUNK_PREAMBLE_SIZE; |
| |
| if (chunk_size > MAX_CODEBOOK_SIZE - s->next_codebook_buffer_index) { |
| av_log(s->avctx, AV_LOG_ERROR, "cbp0 chunk too large (0x%X bytes)\n", chunk_size); |
| return; |
| } |
| |
| /* accumulate partial codebook */ |
| memcpy(&s->next_codebook_buffer[s->next_codebook_buffer_index], |
| &s->buf[cbp0_chunk], chunk_size); |
| s->next_codebook_buffer_index += chunk_size; |
| |
| s->partial_countdown--; |
| if (s->partial_countdown == 0) { |
| |
| /* time to replace codebook */ |
| memcpy(s->codebook, s->next_codebook_buffer, |
| s->next_codebook_buffer_index); |
| |
| /* reset accounting */ |
| s->next_codebook_buffer_index = 0; |
| s->partial_countdown = s->partial_count; |
| } |
| } |
| |
| if (cbpz_chunk != -1) { |
| |
| chunk_size = AV_RB32(&s->buf[cbpz_chunk + 4]); |
| cbpz_chunk += CHUNK_PREAMBLE_SIZE; |
| |
| if (chunk_size > MAX_CODEBOOK_SIZE - s->next_codebook_buffer_index) { |
| av_log(s->avctx, AV_LOG_ERROR, "cbpz chunk too large (0x%X bytes)\n", chunk_size); |
| return; |
| } |
| |
| /* accumulate partial codebook */ |
| memcpy(&s->next_codebook_buffer[s->next_codebook_buffer_index], |
| &s->buf[cbpz_chunk], chunk_size); |
| s->next_codebook_buffer_index += chunk_size; |
| |
| s->partial_countdown--; |
| if (s->partial_countdown == 0) { |
| |
| /* decompress codebook */ |
| decode_format80(s->next_codebook_buffer, |
| s->next_codebook_buffer_index, |
| s->codebook, s->codebook_size, 0); |
| |
| /* reset accounting */ |
| s->next_codebook_buffer_index = 0; |
| s->partial_countdown = s->partial_count; |
| } |
| } |
| } |
| |
| static int vqa_decode_frame(AVCodecContext *avctx, |
| void *data, int *data_size, |
| const uint8_t *buf, int buf_size) |
| { |
| VqaContext *s = avctx->priv_data; |
| |
| s->buf = buf; |
| s->size = buf_size; |
| |
| if (s->frame.data[0]) |
| avctx->release_buffer(avctx, &s->frame); |
| |
| if (avctx->get_buffer(avctx, &s->frame)) { |
| av_log(s->avctx, AV_LOG_ERROR, " VQA Video: get_buffer() failed\n"); |
| return -1; |
| } |
| |
| vqa_decode_chunk(s); |
| |
| /* make the palette available on the way out */ |
| memcpy(s->frame.data[1], s->palette, PALETTE_COUNT * 4); |
| s->frame.palette_has_changed = 1; |
| |
| *data_size = sizeof(AVFrame); |
| *(AVFrame*)data = s->frame; |
| |
| /* report that the buffer was completely consumed */ |
| return buf_size; |
| } |
| |
| static av_cold int vqa_decode_end(AVCodecContext *avctx) |
| { |
| VqaContext *s = avctx->priv_data; |
| |
| av_free(s->codebook); |
| av_free(s->next_codebook_buffer); |
| av_free(s->decode_buffer); |
| |
| if (s->frame.data[0]) |
| avctx->release_buffer(avctx, &s->frame); |
| |
| return 0; |
| } |
| |
| AVCodec vqa_decoder = { |
| "vqavideo", |
| CODEC_TYPE_VIDEO, |
| CODEC_ID_WS_VQA, |
| sizeof(VqaContext), |
| vqa_decode_init, |
| NULL, |
| vqa_decode_end, |
| vqa_decode_frame, |
| CODEC_CAP_DR1, |
| .long_name = NULL_IF_CONFIG_SMALL("Westwood Studios VQA (Vector Quantized Animation) video"), |
| }; |
