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authorMike Melanson <mike@multimedia.cx>2003-10-02 05:20:07 +0000
committerMike Melanson <mike@multimedia.cx>2003-10-02 05:20:07 +0000
commit6955a88293ea3dc98beb31f43993b7cd6a24b4c9 (patch)
treec8c0ce37607445fa74bf6e16481b625c6c132c1a /libavcodec/vqavideo.c
parentec59fd536f93fdca464ac9cbe423647c96bf69c0 (diff)
first pass at a VQA video decoder
Originally committed as revision 2332 to svn://svn.ffmpeg.org/ffmpeg/trunk
Diffstat (limited to 'libavcodec/vqavideo.c')
-rw-r--r--libavcodec/vqavideo.c610
1 files changed, 610 insertions, 0 deletions
diff --git a/libavcodec/vqavideo.c b/libavcodec/vqavideo.c
new file mode 100644
index 0000000000..bc6d33c872
--- /dev/null
+++ b/libavcodec/vqavideo.c
@@ -0,0 +1,610 @@
+/*
+ * Westwood Studios VQA Video Decoder
+ * Copyright (C) 2003 the ffmpeg project
+ *
+ * This library 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 of the License, or (at your option) any later version.
+ *
+ * This library 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 this library; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ *
+ */
+
+/**
+ * @file vqavideo.c
+ * VQA Video Decoder by Mike Melanson (melanson@pcisys.net)
+ * For more information about the RPZA format, visit:
+ * http://www.pcisys.net/~melanson/codecs/
+ *
+ * The VQA video decoder outputs PAL8 colorspace data.
+ *
+ * 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 8-50 VQHD chunk data
+ *
+ * Bytes 8-50 are what this decoder expects to see.
+ *
+ * Briefly, VQA is a vector quantized animation format that operates in a
+ * 6-bit 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 indices. If the 12-bit indices 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, the 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 "common.h"
+#include "avcodec.h"
+#include "dsputil.h"
+
+#define PALETTE_COUNT 256
+#define VQA_HEADER_SIZE 0x2A
+#define CHUNK_PREAMBLE_SIZE 8
+
+/* v1, v2 files: each vector codebook entry is 4x2=8 pixels = 8 bytes */
+#define V1_2_VECTOR_SIZE 8
+#define V1_2_MAX_VECTORS 0xF00
+/* v3 files: each vector codebook entry is 4x4=16 pixels = 16 bytes */
+#define V3_VECTOR_SIZE 16
+#define V3_MAX_VECTORS 0xFF00
+
+#define LE_16(x) ((((uint8_t*)(x))[1] << 8) | ((uint8_t*)(x))[0])
+#define BE_16(x) ((((uint8_t*)(x))[0] << 8) | ((uint8_t*)(x))[1])
+#define BE_32(x) ((((uint8_t*)(x))[0] << 24) | \
+ (((uint8_t*)(x))[1] << 16) | \
+ (((uint8_t*)(x))[2] << 8) | \
+ ((uint8_t*)(x))[3])
+
+#define FOURCC_TAG( ch0, ch1, ch2, ch3 ) \
+ ( (long)(unsigned char)(ch3) | \
+ ( (long)(unsigned char)(ch2) << 8 ) | \
+ ( (long)(unsigned char)(ch1) << 16 ) | \
+ ( (long)(unsigned char)(ch0) << 24 ) )
+
+#define CBF0_TAG FOURCC_TAG('C', 'B', 'F', '0')
+#define CBFZ_TAG FOURCC_TAG('C', 'B', 'F', 'Z')
+#define CBP0_TAG FOURCC_TAG('C', 'B', 'P', '0')
+#define CBPZ_TAG FOURCC_TAG('C', 'B', 'P', 'Z')
+#define CPL0_TAG FOURCC_TAG('C', 'P', 'L', '0')
+#define CPLZ_TAG FOURCC_TAG('C', 'P', 'L', 'Z')
+#define VPTZ_TAG FOURCC_TAG('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;
+ DSPContext dsp;
+ AVFrame frame;
+
+ unsigned char *buf;
+ int size;
+
+ unsigned char palette[PALETTE_COUNT * 4];
+
+ 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 */
+ 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 int vqa_decode_init(AVCodecContext *avctx)
+{
+ VqaContext *s = (VqaContext *)avctx->priv_data;
+ unsigned char *vqa_header;
+
+ s->avctx = avctx;
+ avctx->pix_fmt = PIX_FMT_PAL8;
+ avctx->has_b_frames = 0;
+ dsputil_init(&s->dsp, avctx);
+
+ /* make sure the extradata made it */
+ if (s->avctx->extradata_size != VQA_HEADER_SIZE) {
+ printf(" 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 = LE_16(&vqa_header[6]);
+ s->height = LE_16(&vqa_header[8]);
+ 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;
+ }
+
+ /* allocate codebooks */
+ if (s->vqa_version == 3) {
+ s->codebook = av_malloc(V3_VECTOR_SIZE * V3_MAX_VECTORS);
+ s->next_codebook_buffer = av_malloc(V3_VECTOR_SIZE * V3_MAX_VECTORS);
+ } else {
+ s->codebook = av_malloc(V1_2_VECTOR_SIZE * V1_2_MAX_VECTORS);
+ s->next_codebook_buffer = av_malloc(V1_2_VECTOR_SIZE * V1_2_MAX_VECTORS);
+ }
+ 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) { \
+ printf ("vqavideo: decode_format80 problem: next op would overflow dest_index\n"); \
+ printf ("vqavideo: current dest_index = %d, count = %d, dest_size = %d\n", \
+ dest_index, count, dest_size); \
+ return; \
+ }
+
+static void decode_format80(unsigned char *src, int src_size,
+ unsigned char *dest, int dest_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) {
+ printf ("vqavideo: decode_format80 problem: dest_index (%d) exceeded dest_size (%d)\n",
+ dest_index, dest_size);
+ return;
+ }
+
+ if (src[src_index] == 0xFF) {
+
+ src_index++;
+ count = LE_16(&src[src_index]);
+ src_index += 2;
+ src_pos = LE_16(&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 = LE_16(&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 = LE_16(&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 = BE_16(&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;
+ }
+ }
+
+ if (dest_index < dest_size)
+ printf ("vqavideo: decode_format80 problem: decode finished with dest_index (%d) < dest_size (%d)\n",
+ dest_index, dest_size);
+}
+
+static void vqa_decode_chunk(VqaContext *s)
+{
+
+//static int frame = 0;
+ unsigned int chunk_type;
+ unsigned int chunk_size;
+ int byte_skip;
+ unsigned int index = 0;
+ int i;
+ unsigned char r, g, b;
+ unsigned int *palette32;
+
+ 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;
+
+//printf (" **** decoding frame #%d, stride = %d\n", frame++, s->frame.linesize[0]);
+ /* first, traverse through the frame and find the subchunks */
+ while (index < s->size) {
+
+ chunk_type = BE_32(&s->buf[index]);
+ chunk_size = BE_32(&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:
+ printf (" 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 */
+ printf (" 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 = BE_32(&s->buf[cpl0_chunk + 4]);
+ /* sanity check the palette size */
+ if (chunk_size / 3 > 256) {
+ printf ("vqavideo: problem: found a palette chunk with %d colors\n",
+ chunk_size / 3);
+ return;
+ }
+ cpl0_chunk += CHUNK_PREAMBLE_SIZE;
+ palette32 = (unsigned int *)s->palette;
+ 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;
+ palette32[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 */
+ printf (" VQA video: problem: found both CBF0 and CBFZ chunks\n");
+ return;
+ }
+
+ /* decompress the full codebook chunk into the codebook accumulation
+ * buffer; this is safe since only the first frame is supposed to have
+ * a full codebook */
+ if (cbfz_chunk != -1) {
+
+/* yet to be handled */
+
+ }
+
+ /* copy a full codebook */
+ if (cbf0_chunk != -1) {
+
+ index = cbf0_chunk;
+
+ chunk_size = BE_32(&s->buf[cbf0_chunk + 4]);
+ /* sanity check the full codebook size */
+ if (s->vqa_version == 3) {
+ if (chunk_size / (V3_VECTOR_SIZE) > V3_MAX_VECTORS) {
+ printf (" VQA video: problem: CBF0 chunk too large (0x%X bytes)\n",
+ chunk_size);
+ return;
+ }
+ } else {
+ if (chunk_size / (V1_2_VECTOR_SIZE) > V1_2_MAX_VECTORS) {
+ printf (" 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 */
+ printf (" VQA video: problem: no VPTZ chunk found\n");
+ return;
+ }
+
+ /* decode frame */
+ chunk_size = BE_32(&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);
+
+
+if (0)
+{
+int count = 0;
+printf (" finished decoding frame...");
+for (index = 8000; index < 16000; index++)
+ if (s->decode_buffer[index] > 0x0F)
+ count++;
+printf (" %d/8000 hibytes exceeded 0x0F\n", count);
+}
+
+
+ /* render the final PAL8 frame */
+ 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) */
+ lines = 0;
+ break;
+
+ case 2:
+ lobyte = s->decode_buffer[lobytes];
+ hibyte = s->decode_buffer[hibytes];
+ if (hibyte > 0x0F) {
+ printf (" VQA video: problem: vector #%d/%d high byte out of range (0x%X >= 0x0F)\n",
+ lobytes, s->decode_buffer_size / 2, hibyte);
+ hibyte = lobyte = 0;
+ } else if (hibyte == 0x0F)
+ hibyte = 0;
+ vector_index = (hibyte << 8) | lobyte;
+ vector_index *= V1_2_VECTOR_SIZE;
+ lines = 2;
+ 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 */
+ printf (" VQA video: problem: found both CBP0 and CBPZ chunks\n");
+ return;
+ }
+
+ if (cbp0_chunk != -1) {
+
+ chunk_size = BE_32(&s->buf[cbp0_chunk + 4]);
+ cbp0_chunk += CHUNK_PREAMBLE_SIZE;
+
+ /* 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) {
+
+/* more partial codebook handling ... */
+
+ }
+}
+
+static int vqa_decode_frame(AVCodecContext *avctx,
+ void *data, int *data_size,
+ uint8_t *buf, int buf_size)
+{
+ VqaContext *s = (VqaContext *)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)) {
+ printf (" 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);
+
+ *data_size = sizeof(AVFrame);
+ *(AVFrame*)data = s->frame;
+
+ /* report that the buffer was completely consumed */
+ return buf_size;
+}
+
+static int vqa_decode_end(AVCodecContext *avctx)
+{
+ VqaContext *s = (VqaContext *)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,
+};