This codec works on 4x4 pixel tiles, which can be generated and also
read from the datastream. Codec5 does not recognize the "skip-block"
command; codecs33/34 are the same as 4/5 but with a different tileset
generator.
Signed-off-by: Manuel Lauss <manuel.la...@gmail.com>
---
v2: had left+top swapped resulted in weird visuals in e.g. L5PLAY.ANM
codec33/34 are untested since I have no video files using it. I think
they are used only in the SEGA-CD Version of Rebel Assault 1, along
with codec31/32 which are modifications of codec1. But the latest DOS
EXE had the code in it so I implemented it here as well.
libavcodec/sanm.c | 229 ++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 229 insertions(+)
diff --git a/libavcodec/sanm.c b/libavcodec/sanm.c
index 6080144235..eecfefd43b 100644
--- a/libavcodec/sanm.c
+++ b/libavcodec/sanm.c
@@ -293,6 +293,8 @@ typedef struct SANMVideoContext {
int8_t p8x8glyphs[NGLYPHS][64];
uint8_t c47itbl[0x10000];
uint8_t c23lut[256];
+ uint8_t c4tbl[2][256][16];
+ uint16_t c4param;
} SANMVideoContext;
typedef struct SANMFrameHeader {
@@ -480,6 +482,142 @@ static av_cold int init_buffers(SANMVideoContext *ctx)
return 0;
}
+static void codec33_gen_tiles(SANMVideoContext *ctx, int8_t param1)
+{
+ uint8_t *dst = &(ctx->c4tbl[0][0][0]);
+ int i, j, k, l, m, n, o, p;
+
+ for (i = 0; i < 8; i++) {
+ for (k = 0; k < 8; k++) {
+ j = i + param1;
+ l = k + param1;
+ p = (j + k) / 2;
+ j = (j + p) / 2;
+ m = l / 2;
+ n = (i + param1);
+ o = (k + param1);
+
+ *dst++ = p; *dst++ = p; *dst++ = j; *dst++ = n;
+ *dst++ = p; *dst++ = p; *dst++ = j; *dst++ = i;
+ *dst++ = m; *dst++ = m; *dst++ = p; *dst++ = j;
+ *dst++ = l; *dst++ = l; *dst++ = m; *dst++ = p;
+ }
+ }
+
+ for (i = 0; i < 8; i++) {
+ for (k = 0; k < 8; k++) {
+ j = i + param1;
+ l = k + param1;
+ n = ((j + l) / 2);
+ m = ((l + n) / 2);
+
+ *dst++ = j; *dst++ = j; *dst++ = j; *dst++ = j;
+ *dst++ = n; *dst++ = n; *dst++ = n; *dst++ = n;
+ *dst++ = m; *dst++ = m; *dst++ = m; *dst++ = m;
+ *dst++ = l; *dst++ = l; *dst++ = l; *dst++ = l;
+ }
+ }
+
+ for (i = 0; i < 8; i++) {
+ for (k = 0; k < 8; k++) {
+ j = i + param1;
+ l = k + param1;
+ m = (j + l) / 2;
+ n = (j + m) / 2;
+ o = m / 2;
+ p = j & 0xff;
+
+ *dst++ = p; *dst++ = p; *dst++ = n; *dst++ = m;
+ *dst++ = p; *dst++ = p; *dst++ = n; *dst++ = m;
+ *dst++ = n; *dst++ = n; *dst++ = m; *dst++ = o;
+ *dst++ = m; *dst++ = m; *dst++ = o; *dst++ = l;
+ }
+ }
+
+ for (i = 0; i < 8; i++) {
+ for (k = 0; k < 8; k++) {
+ j = i + param1;
+ l = k + param1;
+ m = (j + l) / 2;
+ n = m / 2;
+
+ *dst++ = j; *dst++ = m; *dst++ = n; *dst++ = l;
+ *dst++ = j; *dst++ = m; *dst++ = n; *dst++ = l;
+ *dst++ = j; *dst++ = m; *dst++ = n; *dst++ = l;
+ *dst++ = j; *dst++ = m; *dst++ = n; *dst++ = l;
+ }
+ }
+}
+
+static void codec4_gen_tiles(SANMVideoContext *ctx, uint16_t param1)
+{
+ uint8_t *dst = &(ctx->c4tbl[0][0][0]);
+ int i, j, k, l, m, n, o;
+
+ for (i = 1; i < 16; i += 2) {
+ for (k = 0; k < 16; k++) {
+ j = i + param1;
+ l = k + param1;
+ m = (j + l) / 2;
+ n = (j + m) / 2;
+ o = (l + m) / 2;
+ if (j == m || l == m) {
+ *dst++ = l; *dst++ = j; *dst++ = l; *dst++ = j;
+ *dst++ = j; *dst++ = l; *dst++ = j; *dst++ = j;
+ *dst++ = l; *dst++ = j; *dst++ = l; *dst++ = j;
+ *dst++ = l; *dst++ = l; *dst++ = j; *dst++ = l;
+ } else {
+ *dst++ = m; *dst++ = m; *dst++ = n; *dst++ = j;
+ *dst++ = m; *dst++ = m; *dst++ = n; *dst++ = j;
+ *dst++ = o; *dst++ = o; *dst++ = m; *dst++ = n;
+ *dst++ = l; *dst++ = l; *dst++ = o; *dst++ = m;
+ }
+ }
+ }
+
+ for (i = 0; i < 16; i += 2) {
+ for (k = 0; k < 16; k++) {
+ j = i + param1;
+ l = k + param1;
+ m = (j + l) / 2;
+ n = (j + m) / 2;
+ o = (l + m) / 2;
+ if (m == j || m == l) {
+ *dst++ = j; *dst++ = j; *dst++ = l; *dst++ = j;
+ *dst++ = j; *dst++ = j; *dst++ = j; *dst++ = l;
+ *dst++ = l; *dst++ = j; *dst++ = l; *dst++ = l;
+ *dst++ = j; *dst++ = l; *dst++ = j; *dst++ = l;
+ } else {
+ *dst++ = j; *dst++ = j; *dst++ = n; *dst++ = m;
+ *dst++ = j; *dst++ = j; *dst++ = n; *dst++ = m;
+ *dst++ = n; *dst++ = n; *dst++ = m; *dst++ = o;
+ *dst++ = m; *dst++ = m; *dst++ = o; *dst++ = l;
+ }
+ }
+ }
+}
+
+
+static int codec4_load_tiles(SANMVideoContext *ctx, uint16_t param2, uint8_t
clr)
+{
+ uint8_t c, *dst = (uint8_t *)&(ctx->c4tbl[1][0][0]);
+ uint32_t loop = param2 * 8;
+
+ if (param2 > 256)
+ return AVERROR_INVALIDDATA;
+
+ if (bytestream2_get_bytes_left(&ctx->gb) < loop)
+ return AVERROR_INVALIDDATA;
+
+ while (loop--) {
+ c = bytestream2_get_byteu(&ctx->gb);
+ *dst++ = (c >> 4) + clr;
+ *dst++ = (c & 0xf) + clr;
+ }
+
+ return 0;
+}
+
static void rotate_bufs(SANMVideoContext *ctx, int rotate_code)
{
if (rotate_code == 2)
@@ -519,6 +657,7 @@ static av_cold int decode_init(AVCodecContext *avctx)
if (ctx->subversion < 2)
ctx->pal[0] = 0xFFU << 24;
}
+ ctx->c4param = 0xffff;
return 0;
}
@@ -532,6 +671,91 @@ static av_cold int decode_end(AVCodecContext *avctx)
return 0;
}
+static int old_codec4(SANMVideoContext *ctx, int top, int left, int w, int h,
+ uint8_t param, uint16_t param2, int codec)
+{
+ const uint16_t p = ctx->pitch;
+ const uint32_t maxpxo = ctx->height * p;
+ uint8_t mask, bits, idx, *gs, *dst = (uint8_t *)ctx->frm0;
+ int i, j, k, l, bit, ret;
+ int32_t pxoff, pxo2;
+
+ if (ctx->c4param != param) {
+ if (codec > 32)
+ codec33_gen_tiles(ctx, param);
+ else
+ codec4_gen_tiles(ctx, param);
+ ctx->c4param = param;
+ }
+ if (param2 > 0) {
+ ret = codec4_load_tiles(ctx, param2, param);
+ if (ret)
+ return ret;
+ }
+
+ if (codec > 32)
+ codec -= 29;
+
+ for (j = 0; j < w; j += 4) {
+ mask = bits = 0;
+ for (i = 0; i < h; i += 4) {
+ pxoff = j + left + ((top + i) * p);
+ if (param2 > 0) {
+ if (bits == 0) {
+ if (bytestream2_get_bytes_left(&ctx->gb) < 1)
+ return AVERROR_INVALIDDATA;
+ mask = bytestream2_get_byteu(&ctx->gb);
+ bits = 8;
+ }
+ bit = !!(mask & 0x80);
+ mask <<= 1;
+ bits--;
+ } else {
+ bit = 0;
+ }
+
+ if (bytestream2_get_bytes_left(&ctx->gb) < 1)
+ return AVERROR_INVALIDDATA;
+ idx = bytestream2_get_byteu(&ctx->gb);
+ if ((bit == 0) && (idx == 0x80) && (codec != 5))
+ continue;
+
+ gs = &(ctx->c4tbl[bit][idx][0]);
+ pxo2 = pxoff;
+ for (k = 0; k < 4; k++) {
+ for (l = 0; l < 4; l++) {
+ if (pxo2 >= 0 && pxo2 < maxpxo) {
+ *(dst + pxo2) = *gs;
+ }
+ gs++;
+ pxo2++;
+ }
+ pxo2 = pxo2 - 4 + p;
+ }
+
+ /* smooth top and left block borders with neighbours */
+ if (((pxoff - p + k) < 0) || ((pxoff - p + k) >= maxpxo)
+ || ((pxoff + 3 * p) < 0) || ((pxoff + 3 * p) >= maxpxo)
+ || (i == 0) || (j == 0))
+ continue;
+ if (param & 0x80) {
+ for (k = 0; k < 4; k++)
+ *(dst + pxoff + k) = ((*(dst + pxoff + k) + *(dst + pxoff
- p + k)) >> 1) | 0x80;
+ *(dst + pxoff + 1 * p) = (*(dst + pxoff + 1 * p) + *(dst +
pxoff + 1 * p - 1)) >> 1 | 0x80;
+ *(dst + pxoff + 2 * p) = (*(dst + pxoff + 2 * p) + *(dst +
pxoff + 2 * p - 1)) >> 1 | 0x80;
+ *(dst + pxoff + 3 * p) = (*(dst + pxoff + 3 * p) + *(dst +
pxoff + 3 * p - 1)) >> 1 | 0x80;
+ } else {
+ for (k = 0; k < 4; k++)
+ *(dst + pxoff + k) = ((*(dst + pxoff + k) + *(dst + pxoff
- p + k)) >> 1) & 0x7f;
+ *(dst + pxoff + 1 * p) = (*(dst + pxoff + 1 * p) + *(dst +
pxoff + 1 * p - 1)) >> 1;
+ *(dst + pxoff + 2 * p) = (*(dst + pxoff + 2 * p) + *(dst +
pxoff + 2 * p - 1)) >> 1;
+ *(dst + pxoff + 3 * p) = (*(dst + pxoff + 3 * p) + *(dst +
pxoff + 3 * p - 1)) >> 1;
+ }
+ }
+ }
+ return 0;
+}
+
static int rle_decode(SANMVideoContext *ctx, uint8_t *dst, const int out_size)
{
int opcode, color, run_len, left = out_size;
@@ -1436,6 +1660,11 @@ static int process_frame_obj(SANMVideoContext *ctx)
return old_codec1(ctx, top, left, w, h, codec == 3);
case 2:
return old_codec2(ctx, top, left, w, h);
+ case 4:
+ case 5:
+ case 33:
+ case 34:
+ return old_codec4(ctx, top, left, w, h, param, parm2, codec);
case 21:
return old_codec21(ctx, top, left, w, h);
case 23:
--
2.48.1
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