pamdec: fix mono support.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>

libavcodec/pnm.c

@@ -112,7 +112,7 @@ int ff_pnm_decode_header(AVCodecContext *avctx, PNMContext * const s)
         s->maxval     = maxval;
         if (depth == 1) {
             if (maxval == 1) {
-                avctx->pix_fmt = PIX_FMT_MONOWHITE;
+                avctx->pix_fmt = PIX_FMT_MONOBLACK;
             } else if (maxval == 255) {
                 avctx->pix_fmt = PIX_FMT_GRAY8;
             } else {
@@ -148,7 +148,7 @@ int ff_pnm_decode_header(AVCodecContext *avctx, PNMContext * const s)
     avctx->height = atoi(buf1);
     if(avctx->height <= 0 || av_image_check_size(avctx->width, avctx->height, 0, avctx))
         return -1;
-    if (avctx->pix_fmt != PIX_FMT_MONOWHITE) {
+    if (avctx->pix_fmt != PIX_FMT_MONOWHITE && avctx->pix_fmt != PIX_FMT_MONOBLACK) {
         pnm_get(s, buf1, sizeof(buf1));
         s->maxval = atoi(buf1);
         if (s->maxval <= 0) {

libavcodec/pnmdec.c

@@ -108,20 +108,21 @@ static int pnm_decode_frame(AVCodecContext *avctx, void *data,
         linesize = p->linesize[0];
         if (s->bytestream + n * avctx->height > s->bytestream_end)
             return -1;
-        if(s->type < 4){
+        if(s->type < 4 || (is_mono && s->type==7)){
             for (i=0; i<avctx->height; i++) {
                 PutBitContext pb;
                 init_put_bits(&pb, ptr, linesize);
                 for(j=0; j<avctx->width * components; j++){
                     unsigned int c=0;
                     int v=0;
+                    if(s->type < 4)
                     while(s->bytestream < s->bytestream_end && (*s->bytestream < '0' || *s->bytestream > '9' ))
                         s->bytestream++;
                     if(s->bytestream >= s->bytestream_end)
                         return -1;
                     if (is_mono) {
                         /* read a single digit */
-                        v = (*s->bytestream++) - '0';
+                        v = (*s->bytestream++)&1;
                     } else {
                         /* read a sequence of digits */
                         do {
@@ -260,7 +261,7 @@ AVCodec ff_pam_decoder = {
     .close          = ff_pnm_end,
     .decode         = pnm_decode_frame,
     .capabilities   = CODEC_CAP_DR1,
-    .pix_fmts  = (const enum PixelFormat[]){PIX_FMT_RGB24, PIX_FMT_RGB32, PIX_FMT_GRAY8, PIX_FMT_MONOWHITE, PIX_FMT_NONE},
+    .pix_fmts  = (const enum PixelFormat[]){PIX_FMT_RGB24, PIX_FMT_RGB32, PIX_FMT_GRAY8, PIX_FMT_MONOBLACK, PIX_FMT_NONE},
     .long_name = NULL_IF_CONFIG_SMALL("PAM (Portable AnyMap) image"),
 };
 #endif