static Expr* env_values(Expr* args) {
assert(args);
if(args == EMPTY_LIST) return scm_mk_error("env-values expects an argument");
if(scm_cdr(args) != EMPTY_LIST) return scm_mk_error("env-values expects only 1 argument");
Expr* fst = scm_car(args);
if(fst == FALSE) return EMPTY_LIST;
if(!scm_is_env(fst)) return scm_mk_error("env-values expects an environment");
return scm_caddr(fst);
}
static void image_setup(SCM scm_type, enum AVPixelFormat *format, int *width, int *height,
uint8_t *data[], int32_t pitches[], void *ptr)
{
int i;
int64_t offsets[8];
memset(offsets, 0, sizeof(offsets));
*format = scm_to_int(scm_car(scm_type));
*width = scm_to_int(scm_cadadr(scm_type));
*height = scm_to_int(scm_caadr(scm_type)),
scm_to_long_array(scm_caddr(scm_type), offsets);
scm_to_int_array(scm_cadddr(scm_type), pitches);
for (i=0; i<8; i++) data[i] = (uint8_t *)ptr + offsets[i];
}
static Expr* str_set(Expr* args) {
assert(args);
if(scm_list_len(args) != 3) return scm_mk_error("string-set! expects 2 args");
Expr* a = scm_car(args);
if(!scm_is_string(a)) return scm_mk_error("string-set! expects a string as its 1st arg");
Expr* i = scm_cadr(args);
if(!scm_is_int(i)) return scm_mk_error("string-set! expects an int as its 2nd arg");
Expr* c = scm_caddr(args);
if(!scm_is_char(c)) return scm_mk_error("string-set! expects a char as its 3rd arg");
scm_sval(a)[scm_ival(i)] = scm_cval(c);
return EMPTY_LIST;
}
SCM make_ffmpeg_output(SCM scm_file_name,
SCM scm_format_name,
SCM scm_video_parameters,
SCM scm_have_video,
SCM scm_audio_parameters,
SCM scm_have_audio,
SCM scm_debug)
{
SCM retval;
struct ffmpeg_t *self;
scm_dynwind_begin(0);
const char *file_name = scm_to_locale_string(scm_file_name);
scm_dynwind_free(file_name);
self = (struct ffmpeg_t *)scm_gc_calloc(sizeof(struct ffmpeg_t), "ffmpeg");
self->video_stream_idx = -1;
self->audio_stream_idx = -1;
SCM_NEWSMOB(retval, ffmpeg_tag, self);
int err;
const char *format_name = NULL;
if (!scm_is_false(scm_format_name)) {
format_name = scm_to_locale_string(scm_symbol_to_string(scm_format_name));
scm_dynwind_free(format_name);
};
#ifdef HAVE_AVFORMAT_ALLOC_OUTPUT_CONTEXT2
err = avformat_alloc_output_context2(&self->fmt_ctx, NULL, format_name, file_name);
if (!self->fmt_ctx) {
ffmpeg_destroy(retval);
scm_misc_error("make-ffmpeg-output", "Error initializing output format for file '~a': ~a",
scm_list_2(scm_file_name, get_error_text(err)));
};
#else
AVOutputFormat *format;
if (format_name)
format = av_guess_format(format_name, NULL, NULL);
else
format = av_guess_format(NULL, file_name, NULL);
if (!format) {
ffmpeg_destroy(retval);
scm_misc_error("make-ffmpeg-output", "Unable to determine file format for file '~a'",
scm_list_1(scm_file_name));
};
self->fmt_ctx = avformat_alloc_context();
if (!self->fmt_ctx) {
ffmpeg_destroy(retval);
scm_misc_error("make-ffmpeg-output", "Error initializing output format for file '~a'",
scm_list_1(scm_file_name));
};
self->fmt_ctx->oformat = format;
strncpy(self->fmt_ctx->filename, file_name, sizeof(self->fmt_ctx->filename));
#endif
char have_video = scm_is_true(scm_have_video);
if (have_video) {
// Open codec and video stream
enum AVCodecID video_codec_id = self->fmt_ctx->oformat->video_codec;
AVCodec *video_encoder = find_encoder(retval, video_codec_id, "video");
AVStream *video_stream = open_output_stream(retval, video_encoder, &self->video_stream_idx, "video", scm_file_name);
// Get video parameters
SCM scm_shape = scm_car(scm_video_parameters);
SCM scm_frame_rate = scm_cadr(scm_video_parameters);
SCM scm_video_bit_rate = scm_caddr(scm_video_parameters);
SCM scm_aspect_ratio = scm_cadddr(scm_video_parameters);
// Configure the output video codec
self->video_codec_ctx =
configure_output_video_codec(video_stream, video_codec_id, scm_video_bit_rate, scm_shape, scm_frame_rate, scm_aspect_ratio);
// Some formats want stream headers to be separate.
if (self->fmt_ctx->oformat->flags & AVFMT_GLOBALHEADER)
self->video_codec_ctx->flags |= AV_CODEC_FLAG_GLOBAL_HEADER;
// Open output video codec
open_codec(retval, self->video_codec_ctx, video_encoder, "video", scm_file_name);
// Allocate frame
self->video_target_frame = allocate_output_video_frame(retval, self->video_codec_ctx);
};
char have_audio = scm_is_true(scm_have_audio);
if (have_audio) {
// Open audio codec and stream
enum AVCodecID audio_codec_id = self->fmt_ctx->oformat->audio_codec;
AVCodec *audio_encoder = find_encoder(retval, audio_codec_id, "audio");
AVStream *audio_stream = open_output_stream(retval, audio_encoder, &self->audio_stream_idx, "audio", scm_file_name);
// Get audio parameters
SCM scm_select_rate = scm_car(scm_audio_parameters);
SCM scm_channels = scm_cadr(scm_audio_parameters);
SCM scm_audio_bit_rate = scm_caddr(scm_audio_parameters);
SCM scm_select_format = scm_cadddr(scm_audio_parameters);
// Configure the output audio codec
self->audio_codec_ctx =
configure_output_audio_codec(retval, audio_stream, audio_codec_id,
scm_select_rate, scm_channels, scm_audio_bit_rate, scm_select_format);
// Some formats want stream headers to be separate.
if (self->fmt_ctx->oformat->flags & AVFMT_GLOBALHEADER)
self->audio_codec_ctx->flags |= AV_CODEC_FLAG_GLOBAL_HEADER;
// Open output audio codec
open_codec(retval, self->audio_codec_ctx, audio_encoder, "audio", scm_file_name);
// Allocate audio frame
self->audio_target_frame =
allocate_output_audio_frame(retval, self->audio_codec_ctx, self->audio_codec_ctx->sample_fmt);
self->audio_packed_frame =
allocate_output_audio_frame(retval, self->audio_codec_ctx, av_get_packed_sample_fmt(self->audio_codec_ctx->sample_fmt));
// Initialise audio buffer
ringbuffer_init(&self->audio_buffer, 1024);
};
if (scm_is_true(scm_debug)) av_dump_format(self->fmt_ctx, 0, file_name, 1);
// Open the output file if needed
if (!(self->fmt_ctx->oformat->flags & AVFMT_NOFILE)) {
int err = avio_open(&self->fmt_ctx->pb, file_name, AVIO_FLAG_WRITE);
if (err < 0) {
ffmpeg_destroy(retval);
scm_misc_error("make-ffmpeg-output", "Could not open '~a': ~a",
scm_list_2(scm_file_name, get_error_text(err)));
}
self->output_file = 1;
}
// Write video file header
err = avformat_write_header(self->fmt_ctx, NULL);
if (err < 0) {
ffmpeg_destroy(retval);
scm_misc_error("make-ffmpeg-output", "Error writing header of video '~a': ~a",
scm_list_2(scm_file_name, get_error_text(err)));
};
self->header_written = 1;
scm_dynwind_end();
return retval;
}
